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® Life of Fred Calculus Expanded Edition Stanley F. Schmidt, Ph.D. Polka Dot Publishing

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Page 1: Life of Fred · hands, you will need two reading speeds: thirty minutes per page when ... theorem proof corollary definition lemma theorem proof definition... with such a lack of

®Life of Fred

CalculusExpanded Edition

Stanley F. Schmidt, Ph.D.

Polka Dot Publishing

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What Calculus Is About

I remember standing in the college bookstore at the beginning of myfreshman year. I pulled a beginning calculus textbook off the shelf andopened it. What a frightening sight it was.

The pages were filled with strange symbolism like ∫2

x = 0

(4 – x2) dx

and ∂ φ ∂x

= M. It might as well have been in Turkish. No one else in my

family had ever studied calculus, so there was no one to give me anoverview of what lay ahead. All I was told was that anyone who wanted tostudy any of the topics that I was even remotely interested in would wantto have a grounding in calculus. Even business majors going on for amaster’s degree were required to study it.

But that didn’t tell me what it was. I looked at some of theproblems in that old textbook:

11. Find dy/dx for y = sin x.

18. Determine the eccentricity of (y + 5)² + 4(x – 5)² = 1.

22. Solve y' = tanh x

From my trig class I recognized “sin x” and knew that it didn’t havetheological overtones in this context. But I was still at a loss as to whatcalculus was about or why I needed to learn it. Was this stuff useful? Would I find a need for it in my everyday life?

Yes. The book you now hold in your hands shows that everyaspect of calculus can arise in the course of daily living. If you’ve everfallen into a vat of cheese soup (Chapter 19) or tried to run a thousandpounds of ammo through a customs station (Chapter 9) you know what Imean.

So what’s calculus? In a sentence: If it moves at a varying speed, if it has a curvy shape, if it has a maximum that you’d like to find, or if it involves adding up an infinite number of terms,

then you’re probably looking at calculus.

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A Note to Students

Hi! This is going to be fun.

When I studied calculus my teacher told the class that we couldreasonably expect to spend thirty minutes per page to master the materialin the old calculus book we used. With the book you are holding in yourhands, you will need two reading speeds: thirty minutes per page whenyou’re learning calculus and whatever speed feels good when you’reenjoying the life adventures of Fred.

This book has five parts to it:

1. The life adventures of Fred2. Your Turn to Play

3. Further Ado

4. Answers5. Index

Start on the first page of the life adventures of Fred and things willexplain themselves nicely.

After 24 chapters you will have mastered all of lower-division(freshman and sophomore) calculus.

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A Note to Teachers

This book wasn’t written with you in mind. Instead it was created forthose who will be learning calculus from it. There are a thousandbanal, dignified calculus books with their overwhelming sense of

restraint and propriety that present the material as it has always beenpresented:

definitiontheoremproofcorollarydefinitionlemmatheoremproofdefinition...

with such a lack of excitement that even a rock would be bored.

There is no reason why the study of calculus should have sufferingas its dominant motif—as if our students were children in some Dickensnovel. Not withstanding any objections of the American DentalAssociation, a spoonful of sugar really doesn’t do any harm. In the years Itaught calculus, I often looked out at the faces of the students and thoughtto myself that these individuals are not just Homo habilis (the toolmaker,the worker) but Homo ludens (the playful).

This text will also make your life more pleasant. You haven’t beenforgotten. Here are some secrets between you and me:

1. Cities will be your real friend. Six cities are found at the end of

each chapter in the main text. Each city is a set of problems andquestions which may take your students 20–30 minutes to workthrough. You can assign one or more of the cities as homework. In this Expanded Edition all of the answers to the problems in Cities

are supplied. They will have immediate feedback as to whetherthey’ve mastered the material.

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2. The main meat of calculus is found in the first section of thebook which tells of the life adventures of Fred and in theYour Turn

to Play which contains lots of completely-worked-out problems.

Many instructors assign the problems from theYour Turn to Play

section. These provide the graded exercises that many beginningstudents require before tackling the more substantial problems inCities. (Your Turn to Play begins at page A-401.)

3. You can make this course as high-powered as you wish byincluding whatever material you like from the Further Ado section.

(Further Ado begins at page B-441.)

4. Every calculus book leaves out some topics. Very few are leftout of Life of Fred. (Check the index for your favorite topics.)

Furthermore, there are many ideas/topics/themes/presentations thatcan’t be found anywhere else. The rigor is also here with much ofit in the Further Ado section of the book so that you may decide how

much of it you’ll include in the course you’re teaching.

5. On these pages you and your students will find all of calculusfolded into the story of the early years of Fred. The topics ofcalculus arise naturally out of his life experiences.

➢ When Fred and his doll Kingie are playing on thekitchen floor (while his mother makes cookies) he inventsa game to play with Kingie. That game evolves into theMean Value Theorem.

➢ Visiting the buffet at a casino in Oz, Fred and his friendsencounter hyperbolic trig functions wherever they turn.

➢ Line integrals arise naturally when Fred does someinvestigative work at the law library in his attempt to getexpelled from kindergarten.

You might enjoy this book as much as your students do!

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Contents

(Topics in small italics are covered in the Further Ado section of the book at

the page numbers indicated.)

Chapter 1 Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Domain, Codomain, Range, Onto

Chapter 2 Limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27ε-δ definition 443

Chapter 3 Speed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Average Speed vs. Instantaneous Speed

Chapter 4 Slope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Tangent Lines

Chapter 5 Derivatives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Maximums/MinimumsProduct/Quotient/Chain Rulesproofs of the product/quotient/chain rules 448

Chapter 6 Concavity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Second DerivativesAsymptotes

Chapter 7 Trig.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89Tests for Extrema

Chapter 8 Related Rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103Implicit DifferentiationExplicit/Implicit/Parametric

Chapter 9 Curvature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117Mean Value Theoremproof of the MVT 456L’Hospital rule 458

AccelerationAntiderivatives

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Chapter 10 Integrals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137Fundamental Theorem of Calculusproof of FTC 459

Chapter 11 Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151Parametric Forms for Area and LengthImproper Integrals

Chapter 12 Work. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169Solids of RevolutionTorque

Chapter 13 Centroids. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183DifferentialsAverage Value of a FunctionIntegration by PartsMoments of Inertia

Chapter 14 Logs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199Probability Density Functionsdefinition of e 464bounded increasing sequences 466

Chapter 15 Conics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211Hydrostatic Forceoblique asymptotes 470

Chapter 16 Infinite Series. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225Tests for Convergence

Chapter 17 Solids of Revolution. . . . . . . . . . . . . . . . . . . . . . . . . . . . 246Trig SubstitutionsSurface AreaArc Length

Chapter 18 Polar Coordinates.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263Alternating SeriesPower SeriesEvaluating Integrals Using Substitutionspartial fractions 483

Maclaurin and Taylor Seriesremainder formula for Taylor 485

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Chapter 19 Hyperbolic Trig. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286Separating the Variables in Differential EquationsNumerical Integration

Chapter 20 Vectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305

Chapter 21 Partial Derivatives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319Chain Rule with Intermediate VariablesLagrange multipliers 489

Chapter 22 Double Integrals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337Cylindrical Coordinate Systemspherical coordinates 491

Chapter 23 Vector Calculus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 357GradientDirectional DerivativeLine IntegralsGreen’s Theoremflux of a vector through a surface 497Divergence theorem 505Stokes’s theorem 510

Chapter 24 Differential Equations. . . . . . . . . . . . . . . . . . . . . . . . . . . 381Variables Separableexact and integrating factors 512

Orthogonal TrajectoriesFirst Order LinearBernoulli’s equation 440

Second Order

Your Turn to Play. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-401Further Ado. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-441Answers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-519Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 582

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Chapter OneFunctions

Once upon a time, a long time ago, on the western slopes of theSiberian Mountains, there lived Fred’s parents. However, theyweren’t called Fred’s parents since Fred hadn’t been born yet. But one day, more recently than a long

time ago, the stork delivered Fred. The luckycouple, Mr. & Mrs. Gauss, discovered that theywere his parents.

At least Mrs. Gauss (rhymes with“house”) thought she was a parent. Staring atFred, she chattered, “Oh, isn’t our baby beautiful!”

Mr. Gauss frowned and said, “He doesn’t look a bit like me.” Mrs.Gauss didn’t get the drift of what her husband was saying. She responded,“Of course he doesn’t. He’s just a little baby, all red and wrinkly, and,besides, he was very young when he was born.” Fred’s father rolled backhis eyes, turned, and left the room.

Mrs. Gauss carried him around a while and then, not knowing whatto do with him, put him back in his crib. She had high hopes that her littletyke would grow up to be a country western singer. After she tucked himin, she handed him a new toy. It was a box with three buttons on it. Eachbutton had an animal printed on it.

When Fred hit the button with the dog on it, the box sounded,“Bow-wow!” When he tried the lion, “Roar!” The duck, “Quack!” Thiswas Fred’s first encounter with the idea of function. He found out thatEVERY time he touched the he heard, “Quack!”

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Chapter One Functions

Here is how he summarized in his head what he knew about hisanimal-toy function:

1. There are two sets involved: the set of animal buttons

{dog, lion, duck} and the set of animal sounds {Bow-wow, Roar,

Quack}.

2. Every time I hit the lion I get a sound and it’s always

the same sound.

Fred was fascinated by this idea of function. You start with twosets and for each element of the first set there is exactly one element of thesecond set which corresponded to it. Fred looked around his study (crib)and invented a new function. His first set contained the things in his criband the second set was colors. He saw his sheet and that matched up with“white” in the second set. His matched up with “yellow.” The bars

on his crib also matched up with “yellow.” Can two different things be “yellow”? Yes. The only critical thing

for the idea of a function is that each element in the first set have exactlyone image in the second set. It’s okay if two different elements in the firstset have the same image.

Fred thought to himself This is baby stuff! I’m one day old

and I should be able to think of a more sophisticated example of a

function. He thought of his diaper which was in the shape of a right

triangle. He labeled one of the acute angles with the letter A and created

the following function: For any acute angle A, draw a diaper—I mean a

triangle—with one of the acute angles being A.

A

Then Fred continued measure the length of the side opposite and divide

that length by the length of the hypotenuse. When Fred set angle A equal

to 35º, the result of using his function (namely, drawing a triangle with a35º angle and dividing the opposite side by the hypotenuse) gave him aresult of 0.5735764. Fred was very good at measuring lengths. He called

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Chapter One Functions

this function that he invented the sine function and he wrotesin(35º) = 0.5735764.

But what if he had used a bigger triangle? Would the answer comeout differently? No. He knew he’d get the same answer every time sinceany two right triangles with 35º angles would be similar (something he hadread in his geometry book) and similar triangles are triangles in which thesides are proportional.

Now since every element in the first set, which is the set of allacute angles, has a unique image in the second set, Fred knew that he wasdealing with a genuine function.

When Mrs. Gauss came in to see how Fred was doing, she foundthat he had drawn triangles all over his bed sheets.

As she looked down into Fred’s study and made little “goo-goo-goo” sounds at him, he said, “Mom, let’s play a little game. We’ll call it,Guess the Function.”

Fred continued, “I’m thinking of a function which I’m going to call‘f ’ and I’m going to give you some examples and you try and guess whatthe function is. Are you ready?”

Mrs. Gauss nodded but wasn’t sure what Fred was talking about. Then Fred wrote on a sheet:

f(7) = 15

f(3) = 7

f(6) = 13

f(100) = 201

Mrs. Gauss looked at what he had written. She looked at it for along time. Finally she said, “Are you hungry?”

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Chapter One Functions

Fred shook his head and gave her some more examples:

f(300) = 601 f(12) = 25

f(0) = 1 f(4.5) = 10Finally after waiting several more minutes, he gave her the “hint”:

f (x) = 2x+1.

He tried to explain to her that a function is any rule whichassociates to each element of the first set exactly one element of thesecond set. The object of the game was to guess the rule.

If you would like to play Guess the Function see page A-401 in Your Turn to Play in the back of this book. If you are reading this book to

learn calculus, and not just enjoy the adventures of Fred, every opportunityfor you to takeYour Turn to Play should be taken. The nice part is that

complete solutions are given for all the questions. The Your Turn to Playis one of the easiest ways to learn calculus.

His mother left the room humming a tune that didn’t seem to havea melody. Fred was alone to think functions some more. He wanted toinvent some more of them.

First, I should think of two sets Fred thought and then I’ll

think of a mapping (which is another name for function) between them.

He cast his eyes around the room and spotted a huge stack of old country

western fan magazines that his mom had stacked up in the corner. We’ll let

that be the first set. (The first set is called the domain of a function.)

From his vantage point in his crib he could see part of the kitchen

counter. On it sat a blender, a coffee pot and a mixer. I’ll let these be

the elements of my second set. (The second set is called the codomain of

a function.) Since a function is ANY rule which associates to each element of

the domain, an element of the codomain, Fred could think of hundreds ofpossible functions:

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Chapter One Functions

First example: to every magazine with the letter “R” on the frontcover assign those magazines to the coffee pot and all the rest of themagazines assign to the mixer.

Second example: All magazines less than 50 pages long assign to theblender; those with 50–75 pages assign to the coffee pot and the rest to themixer. Then the image of a magazine with 58 pages would be the coffeepot.

Third example: The oldest magazine (which happened to be the July1952 issue) is assigned to the blender. The youngest magazine is assignedto the coffee pot and all the rest are assigned to the mixer. In this caseevery element of the codomain was the image of at least one element ofthe domain. Such a function is said to be onto the codomain. (In Fred’sfirst example, that function wasn’t onto the codomain since no magazinehad the blender as an image.)

Fourth example: Assign all the magazines to the mixer. This, ofcourse, is not onto the codomain. The set of all images of a function iscalled the range of the function. The range of this function is just themixer. If the range equals the codomain, then the function is onto.

That’s a lot of new words and concepts (unless you had them inyour algebra classes). Let’s turn toYour Turn to Play on page A-402 and

play with those ideas until they become a bit more comfortable.(If you want to read more about functions, see page B-441 in Further

Ado in the back of this book. If you’ll read the first three paragraphs on

that page, it’ll explain what Further Ado is all about.)

If you have a yellow highlighter, please color the duck on theprevious pages.

It’s traveling time. We will have theopportunity to visit six cities in the next severalpages. (If you haven’t looked atYour Turn to Play,

these questions will be tougher than they need tobe.)

Good news! Answers for the Cities are supplied right after the six

Cities. If your purpose is to learn calculus, then do the problems first andthen check your answers.

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Index

1-1 correspondence. . . . . . A-403between the natural numbers

and the rational numbers. . . . . . . . . . . . . . . . B-442

not between the naturalnumbers and the realnumbers. . . . . . . . . B-442

two sets have the samenumber of elements inthem. . . . . . B-441, C-543

absolute maximum.. . . . . . . . . 66absolutely convergent series

. . . . . . . . . . . . . . . . . . 268commutative law does hold

. . . . . . . . . . . . . . . . C-563acceleration. . . . . . . . 126, A-415alternating series. . . . 267, A-429

absolutely convergent series. . . . . . . . . . . . . . . . A-429

conditionally convergentseries. . . . . . . . . . . A-429

convergence. . . . . . . . . . . 267truncating. . . . . . . . . . . A-429

angular speed. . . . . . . . . . . . . 190and related rates. . . . 191, 211

antiderivative. . . . . . . . . . . . . 127guess-and-by-gosh method

. . . . . . . . . . . . . . . . A-427of 1/x.. . . . . . . . . . . . . . . . 202substitutions. . . . . . . . . A-427trig substitution. . . . . . . A-428

applications of integration. . . . . .. . . . . . . . . . . . . . . . . 255, 256

arc length. . . . . . . . . . . . 254, 255cardioid. . . . . . . . . . . . . . . 266in parametric. . . . . . . 159, 255rainbow. . . . . . . . . . . . . . . 161rectangular form. . . . . . . . 159

Archimedes. . . . . . . . . . . . B-506area. . . . . . . . . . . . . . . . . . . A-417

ellipse. . . . . . . . . . . . . . . . 157parametric form. . . . . . . . 157Tinker Creek. . . . . . . . . . . 153under a curve.. . . . . . . . . . 199

area under a curve. 153-154, 255in parametric. . . . . 255, A-418

Aristotle. . . . . . . . . . . . . . . C-536asymptote. . . . . . . . . . 218, A-408

def of horizontal asymptote. . . . . . . . . . . . . . . . B-453

horizontal. . . . . . . . . . . . . . 75oblique. . . . . . . . . 218, B-470vertical. . . . . . . . . . . . . A-408

average value of a function. . . . .. . . . . . . . . . . 186, 256, A-420

BASIC programfor approximating e.. . . B-465for integration. . . . . . . . . . 160for partial sums. . . . . . . . . 231

Bernoulli's equation. . . . . . A-440binomial formula. . . . . . . . B-468boundary conditions. . . . . . . . 386cap. . . . . . . . . . . . . . . . . . . . . . 73cardioid. . . . . . . . . . . 266, A-429

arc length. . . . . . . . . . . . . 266catenary. . . . . . . . . . . . . . . . . 289

582

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Index

center of gravity. . . . . 184, A-419center of mass. . . . . . . . . . . . 184centroid. . . . . . . 184, 256, A-419chain rule. . . . . . . . . . . 64, A-406

proof. . . . . . . . . . . . . . . B-448with several intermediate

variables. . . . . . . 331-332change of variable. . . . . 185, 247chart

delta process. . . 40, 48, 58, 93derivative of 1/x. . . . . . . . 203derivatives.. . . . . . . . . . . . . 64favorite integration

substitutions. . . . . . . . 270implicit vs. explicit. . . . . . 110limit of sine. . . . . . . . . . . . . 29Maclaurin series. . . . . . . . 278Taylor series. . . . . . . . . . . 280three tests for minimums. . 90vertical asymptote. . . . . . . . 81

circle.. . . . . . . . . . . . . . . . . . . 215closed curves. . . . . . . . . . . . . 374closed interval. . . . . . . . . . . . 124codomain. . . . . . . . . . . . . . . . . 18Comparison Test. . . . . . . . . . 233concave. . . . . . . . . . . . . . . . . . 73concavity. . . . . . . . . . . 73, A-408conditionally convergent series

. . . . . . . . . . . . . . . . . . 268commutative law doesn't hold

. . . . . . . . . . . . . . . . C-562cone

definition.. . . . . . . . . . . . . 218filling. . . . . . . . . . . . . . 56, 57

conic sections. . . . . . . 216, A-425in polar. . . . . . . . . . . . . B-481pointed the “wrong way”

. . . . . . . . . . . . . . . . . . 221

rotated. . . . . . . . . . 220, A-425translated.. . . . . . . . . . . . . 220

conservative field. . . . . . . . . . 371constant of integration. . . . . . 193continuous function. . . . . . . . . 33contrapositive. . . . . . . . . . . B-474convergent. . . . . . . . . 229, A-426convex. . . . . . . . . . . . . . . . . . . 73cosh x. . . . . . . . . . . . . 288, A-431

derivative. . . . . . . . . . . . . 291critical points. . . . . . . . . . . . . . 66cross product. . . . . . . . . . . B-509curl F. . . . . . . . . . . . . . . . . B-511curvature. . . . . . 118-119, A-414

formula. . . . . . . . . . . . . . . 120formula (in parametric form)

. . . . . . . . . . . . . . . . . . 121cycloid. . . . . . . . . . . . . . . . . . 110

parametric form. . . . . . B-455cylindrical coordinate system

. . . . . . . . . . . . . . . . . . 350deductive logic. . . . . . . . . . B-474definite integrals.. . . . 193, A-416

evaluating. . . . . . . . . . . . . 143steps to setting them up. . 144

del.. . . . . . . . . . . . . . . . . . . . . 361delta. . . . . . . . . . . . . . . . . . . . . 37delta process.. . . . . . . . . . . 39, 93

for a cubic. . . . . . . . . . . . . . 47for log x. . . . . . . . . . . . . . 203for x to the nth power. . . . . 58for y = 6. . . . . . . . . . . . B-448for y = sin x.. . . . . . . . . . . . 93Your Turn to Play examples

. . . . . . . . . . . . . . . . A-405density

in a solid. . . . . . . . . . . . . . 174

583

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Index

probability density function. . . . . . . . . . . . . . 204-206

variable along a length. . . 141derivative. . . . . . . . . . . . . . . . . 73

arc trig functions. . . . . . . . . 92definition.. . . . . . . . . . . . . . 57dy/dx. . . . . . . . . . . . . . . . . . 57hyperbolic trig functions

. . . . . . . . . . . . 291, A-432in parametric form. . . . . . 111partial. . . . . . . . . . . . . . . . 322sine by delta process. . . . . . 93trig functions.. . . . . . . . . . . . .

. . . . . 91-92, A-409-A410trig functions (applications)

. . . . . . . . . . A-411-A-412variable in the exponent

. . . . . . . . . . . . . . . . . . 206differential equations. . . . . . . . . .

. . . . . . . . . . . . . . . 104, A-432boundary condition. . . . . . 385exact. . . . . . . . . . . . . . . B-512first-order linear. . . . . . A-439homogeneous. . . . . . . . A-437integrating factors . . . B-512,

. . B-514-515, B-517-518mixing problem.. . . . . . . . 389orthogonal trajectory.. . . . 387second order. . . . . . . . . . . 393separating the variables.. . . . .

. . . . . . . . . . . . . . 292, 382variables separable. . . . A-437what lies ahead. . . . . . . B-518

differential form. . . . . 185, B-462direction of maximum change

. . . . . . . . . . . . . . . . . . 361directional derivative. . . . . . . 364

distributivefinite case. . . . . . . . . . . . . 233formulas for vectors. . . . . 314infinite case.. . . . . 233, B-477

div F. . . . . . . . . . . . . . . . . . B-506divergence. . . . . . . . . . . . . B-506divergence theorem. . . . . . B-505divergent. . . . . . . . . . . . . . . . 229diving board (off the). . . 126-127domain of a function. . . . . . . . 28dot product of vectors. . . . . . 310

formulas. . . . . . . . . . . . . . 314double integral. . . . . . 341, A-434

finding area. . . . . . . . . . . . 345finding weight of area with

variable density. . . . . 346moment of inertia. . . . . . . 347torque. . . . . . . . . . . . . . . . 347

Dr. Johnson. . . . . . . . . . . . . . 257ds (arc length).. . . . . . . . . . . . 159

in polar. . . . . . . . . . . . . . . 264dS (surface). . . . . . . . . . . . B-499

in polar. . . . . . . . . . . . . B-503dummy variable. . . . . . . . . . . 295d²y/dx². . . . . . . . . . . . . . . . . . . 73e. . . . . . . . . . . . . . . . . . . . . . . 203

definition.. . . . . B-464-B-465eccentricity

in polar. . . . . . . . . . . . . B-482in rectangular. . . . . . . . B-472

ellipse. . . . . . . . . . . . . . . . . . . 216eccentricity. . . . . . . . . . B-471foci. . . . . . . . . . . . . . . . B-471in polar. . . . . . . . . . . . . B-481parametric form. . . . . . . . 157

energy of rotation. . . . . . . . . . 190

584

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epsilon-delta. . . . . . B-444-B-445arguments using. . . . . B-446,

B-447, B-450, B-451,B-467, B-470, C-520,

C-529, C-535equation of a plane through a

point and normal to avector. . . . . . . . . . . . . 362

exact differential equation. . . . . . . . . . . . . . . . B-512

potential function. . . . . B-512explicit relation. . . . . 108, A-413exponential functions. . . . . A-421extrema.. . . . . . . . . . . . . . . . . . 60first derivative test. . . . . . . . . . 90first moment. . . . . . . . . . . . . . 178first-order linear. . . . . 390, A-439flux of a vector through a surface

. . . . . . . . . . . . . . . . B-497focus. . . . . . . . . . . . . . . . . . . . 216folium of Descartes. . . . . . . . 108function of two variables. . . . 321functions.. . . . . . . . . . . 16, B-441

1-1. . . . . . . . . . . . . . . . . A-403codomain. . . . . . . . . . . . . . 18continuous.. . . . . . . . . . A-404domain. . . . . . . . . . 18, A-402image under a function. . . . 19increasing bounded functions

. . . . . . . . . . . . . . . . B-466inverses. . . . . . . . . . . . . A-403onto. . . . . . . . . . . . . . . . . . . 19ordered pairs definition

. . . . . . . . . . . . . . . . A-403range. . . . . . . . . . . . . . . . . . 19

Fundamental Theorem ofCalculus. . . . . . . 144, 252

needs continuous function. . . . . . . . . . . . . . . . . . 162

proof. . . . . . . . . . . B-459-461Gauss, Karl Friedrich. . . . . B-507Gauss’s theorem.. . . . . . . . B-505general operating rule for doing

integration in polar form. . . . . . . . . . . . . . . . . . 266

geometric series. . . . . . . . . . . 228sum. . . . . . . . . . . . 229, B-473when convergent. . . . . . . . 230

Gödel. . . . . . . . . . . . . . . . . . . 228golden mean. . . . . . . . . . . . C-536Goldilocks. . . . . . . . . . . . . C-536grad u. . . . . . . . . . . . . . . . . . . 360gradient. . . . . . . . . . . . . . . . . . . .

. . . 360, A-435-A-436, B-492length of the vector. . . . . . 363normal to a surface. . . . B-497

gravity (motion under). . . . . . . . .. . . . . . . . . . . . . . . . . 126-127

greatest-integer-in function. . . 44Greek alphabet. . . . . . . . . . . . 295Green, George. . . . . . . . . . . . 373Green’s theorem.. . . . . . . . . . 373Green’s theorem in space

. . . . . . . . . . . . . . . . B-505guess a function. . . . . . 18, A-401guess-and-by-gosh method.. . . . .

. . . . . . . . . . . . . . . 248, A-427homogeneous equations. . . A-437horizontal asymptote. . 75, B-453hydrostatic force.. . . . . . . . . . . . .

. . . . . . . . . . . 213, 256, A-424

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hyperbola. . . . . . . . . . . . . . . . 217asymptotes. . . . . . . . . . . . 218eccentricity. . . . . . . . . . B-471foci. . . . . . . . . . . . . . . . B-471in polar. . . . . . . . . . . . . B-481

hyperbolic trig functions. . . . 288derivatives.. . . . . . . . . . . . 291formulas. . . . . . . . . . . . . . 288

Ice Cream Cone problem (surfaceintegrals). B-501, B-502,

B-504, B-505, B-507image. . . . . . . . . . . . . . . . . . . . 16implications (if–then).. . . . B-474

contrapositive. . . . . . . . B-474converse. . . . . . . . . . . . B-474inverse.. . . . . . . . . 231, B-474

implicit differentiation. . . . . . 108implicit relation. . . . . 108, A-413

finding tangent. . . . . . . . . 108improper integral. . . . . . . . A-418incomplete elliptic integral of the

second kind. . . . . . . . 161indefinite integral. . . . . . . . . . 193inductive reasoning. . . . . . . . . . .

. . . . . . . . . . . . . B-475-B-476infinite series. . . . . . . . . . . A-426

“last term”.. . . . . . . . . . . . 230absolutely convergent series

. . . . . . . . . . . . . . . . . . 268conditionally convergent

series. . . . . . . . . . . . . 268convergent.. . . . . . . . . . . . 229distributive law. . . . . . . . . 233divergent. . . . . . . . . . . . . . 229harmonic series. . . . . . . . . 233integral test. . . . . . . . . . . . 234Limit Comparison Test. . . . . .

. . . . . . . . . . . . 233, B-476

Maclaurin series. . . . . . A-431partial sums.. . . . . . . . . . . 231Ratio Test. . . . . . . . . . . . . 239rules for convergence. . . . . . .

. . . . . . 230, 233-234, 239Taylor series. . . . . 281, A-431

initial condition. . . . . . . . . . . 383instantaneous speed. . . . . . . . . 39integers. . . . . . . . . . . . . . . . B-469Integral Test. . . . . . . . . . . . . . 234integrals

change of variables. . . . . . 247definite. . . . . . . . . 193, A-416favorite integration

substitutions. . . . . . . . 270improper. . . . . . . . . . . . A-418in polar form (general

operating rule). . . . . . 266indefinite. . . . . . . . . . . . . . 193limits. . . . . . . . . . . . . . . A-416line. . . . . . 367, A-436-A-437power series. . . . . . . . . A-430substitutions. . . . . . . . . A-430table of all the applications

. . . . . . . . . . . . . . 255, 256trig substitution. . . . . . . . . . . .

. . . . . . . . 248-250, A-428integrand. . . . . . . . . . . . . . . . 161integrating factors. . . . . . B-514,

B-515, B-517, B-518little black book. . . . . . B-517

integrationchanging the order. . . . B-504over a surface. . . . . . . . B-497

integration by parts.. . 188, A-421proof. . . . . . . . . . . . . . . . . 189used twice. . . . . . . . . . . . . 190

intermediate variables. . . . . . 331

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interval of convergence. . . . . 274differentiating or integrating

within. . . . . . . . . . . . . 275isothermally. . . . . . . . . . . . . . 362iterated integral. . . . . . . . . . . 341kinetic energy. . . . . . . . . . . . . 190Lagrange multipliers. . . . . . . . . .

. . . . . . . . . . . . . . . 328, B-489λ. . . . . . . . . . . . . . . . . . B-490

Law of Cooling. . . . . . . . . . . 385least upper bound. . . . . . . . B-467Leibnitz. . . . . . . . . . . . . . . . . 229lemniscate. . . . . . . . . . . . . . . 264

in polar. . . . . . . . . . . . . . . 264length of a vector. . . . . . . . . . 309length of the gradient vector

. . . . . . . . . . . . . . . . . . 363L’Hospital's rule.. . . . . . . . B-458lim (sin θ)/θ.. . . . . . . . . . . . . . . 93limaçon.. . . . . . . . . . . . . . . A-429limit. . . . . . . . . . . . . . . . . . . . . 32

definition (epsilon–delta). . . . . . . . . . . . . . . . B-443

of a function. . . . . . . . . . . . 28of a product. . . . . . . . . . B-451of a sum. . . . . . . . . . . . B-450one-sided.. . . . . . . . . . . . . 162

Limit Comparison Test. . . . . 233proof. . . . . . . . . . . . . . . B-476

line integral. . 367, A-436, B-492ln x. . . . . . . . . . . . . . . . . . . . . 203local maximum. . . . . . . . . . . . 66logarithmic differentiation

. . . . . . . . . . . . . . . . A-422logistics curve. . . . . . . . . . . . 388logs. . . . . . . . . . . . . . . 203, A-421

definition.. . . . . . . . . . . B-463long-time stories.. . 235-237, 239

M (torque). . . . . . . . . . . . . . . 178Maclaurin series. . . . . 278, A-431mappings. . . . . . . . . . . . . . . . . 18maximums. . . . . . . . . . . . . . . . 60

absolute. . . . . . . . . . . . . . . . 66along curves in a three-

dimensional surface. . . . . . . . . . . . . . . . . . 328

angle of truck sign. . . . . . . 90dog's play area.. . . . . . . . . 140height. . . . . . . . . . . . . . . . 126hemp plant yield. . . . . . . . . 77local. . . . . . . . . . . . . . 66, 321on an interval. . . . . . . . A-407tests for surfaces in three

dimensions. . . . . 323, 327Mean Value Theorem.. . . . . . . . .

. . . . . . . . . . . . . . . 124, A-415proof. . . . . . . . . . . . . . . B-456Rolle's theorem (lemma)

. . . . . . . . . . . . . . . . B-456used for approximation. . . 128

minimums. . . . . . . . . . . . . . . . 60bubbles lost. . . . . . . . . . . . . 89fetching the beer. . . . . . . . . 62paper used. . . . . . . . . . . . . . 78shortest route across the

tundra. . . . . . . . . . . . . . 97sound reaching Fred’s ears

. . . . . . . . . . . . . . . . . . 125mixed partial derivative. . . . . 324moment of inertia. . . . . . . . . . . . .

. . . . . . . . . . . 189, 256, A-421of a banana. . . . . . . . . . . . 190using double integrals. . . . 347

MVT.. . . . . . . . . . . . . 124, A-415proof. . . . . . . . . . . . . . . B-456used for approximation. . . 128

587

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My = Nx.. . . . . . . . . . . . . . . . . 371exact differential equation . . .

. . . . . . . . . . . . . . . . B-512Napier, John. . . . . . C-554, C-561natural logs.. . . . . . . . . . . . . . 203Newton.. . . . . . . 229, 385, B-506normal to a surface.. . . . . . B-497numerical integration. . . . . . . . . .

. . . . . . . . . . . . . . . 294, A-432memory aids. . . . . . . . . . . 299Simpson’s rule. . . . . . . . . 298trapezoidal rule. . . . . . . . . 297

one-sided limit. . . . . . . . . . . . 162one-to-one. . . . . . . . . . . . . A-403open interval.. . . . . . . . . . . . . 124p-series. . . . . . . . . . . . . . . . . . 235Pappus. . . . . . . . . . . . . . . . . . 250Pappus’ theorem.. . . . . . . . . . 250parabola. . . . . . . . . . . . . . . . . 217

in polar. . . . . . . . . . . . . B-481parametric representation.. . 110,

A-413partial derivative. . . . . . . . . . 322partial fractions. . . . . . . . . . . 271

a brush-up. . . . . B-483, B-484path-independent. . . . . . . . . . 376point of inflection.. . . . 74, A-408point-slope equation of the line

. . . . . . . . . . . . . . . . . . . 49polar coordinates. . . . 264, A-429

a brush-up. . . . . B-478, B-480double integration. . . 348-349finding volume. . . . . 348-349formulas. . . . . . . . B-480-482

position vector. . . . . . . . . . B-494potential function. . . . 372, B-492power series. . . . . . . . 272, A-430

interval of convergence.. . 274

Maclaurin. . . . . . . . . . . . . 278Taylor. . . . . . . . . . . . . . . . 281

probability density function. . . . . . . . 204, 256, A-421

product rule. . . . . . . . . 64, A-406proof. . . . . . . . . . . . . . . B-448

Product Rule song. . . . . . . . . . 74projection of a vector. . . . . . . 310

length. . . . . . . . . . . . . . . . 311pure second partial derivative

. . . . . . . . . . . . . . . . . . 324quotient rule . . . . . . . . 64, A-406

proof. . . . . . . . . . . . . . . B-448rabbit and the wall. . . . . . . B-466radian measure. . . . . . . . . . . . . 92

definition.. . . . . . . . . . . B-453dimensionless. . . . . . . . . . 191

radius of convergence. . . . . . 274range.. . . . . . . . . . . . . . . . . . . . 19rational numbers.. . . . . . . . B-469rationalizing the numerator. . 292rectangular rule. . . . . . . . . . . 296related rates. . . . . . . 104, A-412,

A-413, A-417and angular velocity. . . . . . . .

. . . . . . . . . . . . . . 191, 211distance to the Christmas tree

. . . . . . . . . . . . . . . . . . 106of the gas cloud.. . . . . . . . 105of the squab.. . . . . . . . . . . 103silo. . . . . . . . . . . . . . . . . . 154surface area. . . . . . . . . . . . 156Toddy’s body. . . . . . . . . . 155

relative maximum. . . . . . . . . . 65for surfaces in three

dimensions. . . . . . . . . 327Rolle’s theorem. . . . . . . . . B-456Root Test. . . . . . . . . . . . . . . . 239

588

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saddle point. . . . . . . . . . 324-325scalar. . . . . . . . . . . . . . . . . . . 306scalar field. . . . . . . . . . . . . . . 366scalar function. . . . . . . . . . . . 360scalar multiplication.. . . . . . . 306Schröder-Bernstein theorem . . . .

. . . . . . . . . . . . . . . . B-443secant line.. . . . . . . . . . . . . . . . 46second derivative test. . . . . 73, 90second moment. . . . . . . . . . . . . .

. . . . . . . . . . . 189, 256, A-421second order differential

equationslacking the dependent variable

. . . . . . . . . . . . . . . . . . 393lacking the independent

variable.. . . . . . . . . . . 395separating the variables. . . . . . . .

. . . . . . . . . . . . . . . . . 292, 382simple paths. . . . . . . . . . . . . . 374Simpson’s rule. . . . . . . . . . . . 298sinh x. . . . . . . . . . . . . 288, A-431

derivative. . . . . . . . . . . . . 291slope of a line. . . . . . . . . . . B-447slope of tangent line. . . . . . 46-47slopes of tangents to curves

. . . . . . . . . . . . . . . . A-405smooth paths. . . . . . . . . . . . . 374snake (weight). . . . . . . . 141, 143solid of revolution. . . . . . . . . 246speed. . . . . . . . . . . . . . . . . . . . 38

instantaneous. . . . . . . . . . . 39spherical coordinates. . . . . B-491

volume. . . . . . . . . . . . . B-492Stokes’s theorem.. . . . B-510-511surface area. . . . . . . . . . . . A-428

in polar. . . . . . . . . . . . . . . 264of a paint can.. . . . . . 252-253of revolution. . . . . . . 251, 256

surface integral. . . B-497, B-498,B-500, B-502-504

tangent to a curve. . . . . . . . . . . 45curve in implicit form. . . . 108

Taylor series. . . . . . . . 281, A-431remainder formula. . . . B-485

Tinker Creek. . . . . . . . . . . . . 153torque. . . . . . . . . . . . . 177, A-418

of a bar. . . . . . . . . . . . . . . 255of a pb&j sandwich.. . . . . . . .

. . . . . . . . . . . . . . 187, 189tractrix curve. . . . . . . . . . . . . 292transcendental numbers. . . B-469trapezoidal rule.. . . . . . . . . . . 297trig substitutions.. . . . . . 248-250triple integrals. . . . . . . . . . A-435unit tangent vector. . . . . . . B-494unit vector. . . . . . . . . . . . . . . 311

i, j, and k.. . . . . . . . . . . . . 313variable density. . . . . . . . . . . 141variables separable. . . . . . . A-437vector. . . . . . . . . . . . . . . . . . . 306

an algebraic view. . . . . B-486components. . . . . . . . . . B-488dot product. . . . . . . . . . . . 310formulas. . . . . . . . . . 313-314length. . . . . . . . . . . . . . . . 309position vector. . . . . . . B-494projection. . . . . . . . . 310, 312scalar product. . . . . . . . . . 310subtraction. . . . . . . . . . A-432unit. . . . . . . . . . . . . . . . . . 311vector product. . . . . . . . B-509zero vector. . . . . . 313, A-433

vector addition. . . . . . . . . . . . 307an algebraic view. . . . . B-487associative.. . . . . . . . . . . . 308formulas. . . . . . . . . . 313-314

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vector field. . . . . . . . . . . . . . . 366velocity

hitting the ground. . . . . . . 126limiting. . . . . . . . . . . . . . . 289

velocity vector. . . . . . . . . . B-494vertical asymptote. . . . . . . . . . 81vertically simple. . . . . . . . . C-560volume

cylindrical shells method. . . . . . . . . . . . . . . . . . 247

of revolution. . . 173, 176, 255polar coordinates.. . . 348-349solid of revolution.. . . . . . . . .

. . . . . . . . 246, 256, A-418solid with constant height

. . . . . . . . . . . . . . . . . . 339solid with variable height

. . . . . . . . . . . . . . 340, 344spherical coordinates. . B-492

water pressure. . 213, 256, A-424weight of area with variable

density. . . . . . . . . . . . 346weight of length with variable

density. . . . . . . . . . . . 255wire skating. . . . . . . . . . . . . . 253work. . . . . . . . . . . . . . 255, A-418

along a curved path. . . . . . 366compressing a spring. . . . 171defined. . . . . . . . . . . . . . . 169lifting Toddy to Oz. . . . . . . . .

. . . . . . . . . . . . . . 169, 171pumping water out. . 173, 255

x-y-z axes. . . . . . . . . . . . . . . . 320y''. . . . . . . . . . . . . . . . . . . . . . . 73

590