chapter 1 level 0 math 0 faculty of engineering - basic science department- prof h n agiza
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Faculty of Engineering - Basic Science Dept- Prof H N Agiza
• We define run to be the distance we move to the right and rise to be the corresponding distance that the line rises (or falls).
The Slope of a Line :
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Finding the Slope of a Line Through Two PointsExample : Find the slope of the line that passes through the points P(2, 1) and Q(8, 5).
Solution :
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Point-Slope Form of the Equation of a Line• Finding the equation of the line that passes through a given point and
P(, ) has slope m.
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Finding the Equation of a Line with Given Pointand SlopeExample : Find an equation of the line through (1, -3) with slope .
Solution :
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Slope-Intercept Form of the Equation of a Line
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Lines in Slope-Intercept Form
Example : Find the equation of the line with slope 3 and y-intercept -2.
Solution:
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Vertical and Horizontal Lines
If a line is horizontal, its slope is , so its equation is , where b is the y-intercept
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Vertical and Horizontal Lines
• An equation for the vertical line through (3, 5) is x = 3.• An equation for the horizontal line through (8, 2) is y =2.
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Finding the Equation of a Line Parallel to a Given LineExample: Find an equation of the line through the point (5,2) that is parallel to the line
Solution:
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
• Example: Show that the points P(3,3), Q(8,17), and R(11,5)are the vertices of a right triangle.
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Mathematical Notations• Belongs to.• Does not belong to. The complex Numbers.• For all (Universal Quantifier). The open finite interval.
{X R : a < x < b} • Empty set. The closed interval. {X R : a x b} • P P implies Q. The semi-closed interval.
{X R : a x b} • P p if and only if Q. The semi-open interval.
{X R : axb} • Natural Numbers {0,1,2,3,….}. The infinite open interval.
{X R : x a} • The Integers {…,-3,-2,-1,0,1,2,3,} The infinite closed interval.• The Rational Numbers. {X R : x a} • R The Real Numbers.
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
1.1 Sets and Notation• Set : a collection of well defined members or elements.
• A subset: is a sub-collection of a set.
• Example : The sets• A = {x Z : } , B={x Z : } , C={-3,-2,-1,0,1,2,3}
Solution:• The first set is the set of all integers whose square lies
between 1 and 9 inclusive, which is precisely the second set, which again is the third set.
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
• The union of two sets A and B, is the set This is read “A union B.”
• The intersection of two sets A and B, is This is read “A intersection B.”
• The difference of two sets A and B, is This is read “A set minus B.”
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Example : If S ={1, 2, 3, 4, 5} , T={4, 5, 6, 7}, and V = {6, 7, 8}, find the sets S T, S T, and S V.
S T = {1, 2, 3, 4, 5,6,7}
S T = {4 , 5}
S v = Φ
Example :Let A={1,2,3,4,5} , B={1,3,5,7,9} .Find the sets A B
A B = {1,2,3,4,5,6,7,9}
A B = {1, 3, 5}
A B = {2, 4, 6} B A = {7, 9}
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
1.2 Intervals An interval is a subset of the real numbers.
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Example : Graphing Intervals
Express each interval in terms of inequalities, and then graph the interval .
(a)
(b)[1.5, 4]=
(C)
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
• Example :Find the Intersection of this Interval, Graph each set. • The intersection of two intervals consists of the numbers that are in both intervals.
Therefore
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Absolute Value• The absolute value of a number a, denoted by , is the
distance from a to 0 on the real number line.• Distance is always positive or zero, so we have
• Definition of Absolute value If a is a real number , then the absolute value of a is
Example: Evaluating Absolute Values of Numbers
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Distance between points • If a and b are real numbers, then the distance between the points a and
b on the real line is
• Note that
• Example : Distance Between Points The distance between the numbers 8 and 2 is
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Integer Exponents• A product of identical numbers is usually written in exponential notation.
• Exponential notation If a is any real number and n is a positive integer , then the power of a is The number is called the base , and is called the exponent
Example:
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Adding and Subtracting Polynomials• We add and subtract polynomials using the properties of real
numbers .• The idea is to combine like terms ,using the Distributive Property.
• For instance,
• Example: Adding and Subtracting Polynomialsa)Find the sum ()+()
b) Find the difference (()
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Multiplying Polynomials• To find the product of polynomials or other algebraic expressions, we need
to use the Distributive Property repeatedly.
Example: Find the product
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Special Product Formulas
Example : Using the Special Product Formulas
Faculty of Engineering - Basic Science Dept- Prof H N Agiza
Factorization
• We use the Distributive Property to expand algebraic expressions. We sometimes need to reverse this process by factoring an expression as a product of simpler ones.
• We say that and are factors of