function hl
TRANSCRIPT
1.
Given functions f : x Working:
3 l x + 1 and g : x x , find the function (f g) .
Answer: ..................................................................(Total 3 marks)
f ( x) =2. If (a) (b)
x , x + 1 for x 1 and g (x) = (f f )(x), find
g (x) (g g)(2).
Working:
Answers: (a) .................................................................. (b) ..................................................................(Total 3 marks)
1
3.
The function f is defined by
x2 x +1 2 f (x) = x + x + 1(a) (ii) (i) Find an expression for f (x), simplifying your answer.
The tangents to the curve of f (x) at points A and B are parallel to the x-axis. Find the coordinates of A and of B.(5)
(b) (ii) (c)
(i)
Sketch the graph of y = f (x).(5)
Find the x-coordinates of the three points of inflexion on the graph of f.
Find the range of (i) (ii) f; the composite function f f.(5) (Total 15 marks)
2
4.
2 The functions f (x) and g (x) are given by f (x) = x 2 and g (x) = x + x. The function (f g)(x) is defined for x , except for the interval ] a, b [.
(a) (b)
Calculate the value of a and of b. Find the range of f g.
Working:
Answers: (a) .................................................................. (b) ..................................................................(Total 6 marks)
3
5.
3 The function f is defined by f : x x .
Find an expression for g (x) in terms of x in each of the following cases (a) (b) (f g ) (x) = x + 1; (g f ) (x) = x + 1.
Working:
Answers: (a) .................................................................. (b) ..................................................................(Total 6 marks)
4
6.
x The functions f and g are defined by f : x e , g : x x + 2.
(a) (b)
Calculate f (3) g (3). Show that (f g) (3) = ln 3 2. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... .....................................................................................................................................(Total 6 marks)1
1
1
5
7.
x +1 Let f and g be two functions. Given that (f g) (x) = 2 and g (x) = 2x 1, find f (x 3).W o r k i n g :
A
n
s w
e r :(Total 6 marks)
6
8.
The functions f and g are defined by f (x) = 2x 1,
x , x 1. g (x) = x + 1Find the values of x for which ( f g) (x) (g f ) (x). .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
7
9.
(a) The function f is defined by f (x) = (x + 2) 3. The function g is defined by g (x) = ax + b, where a and b are constants. Find the value of a, a > 0 and the corresponding value of b, such that
2
3 . f (g (x)) = 4x + 6x 42
(8)
(b)
The functions h and k are defined by h (x) = 5x + 2 and k (x) = cx x + 2 respectively. Find the value of c such that h (k (x)) = 0 has equal roots.(5) (Total 13 marks)
2
8
10.
The functions f and g are defined as:x f (x) = e , x 0 2
1 , x 3. x +3 g (x) =(a) (b) (c) Find h (x) where h (x) = g f (x).(2)
State the domain of h Find h1
1
(x).(2)
(x).(4)
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 8 marks)
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11.
4 ,x 2 x+2 Let f (x) = and g (x) = x 1.If h = g f, find (a) (b) h (x);(2)
h (x), where h
1
1
is the inverse of h.(4)
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
10
12.
Find r =1 Working:
ln( 2 )50 r
, giving the answer in the form a ln 2, where a
.
Answer: ..........................................................................(Total 6 marks)
13.
Find the largest set of values of x such that the function f given by f (x) = values. W o r k i n g :
8x 4 x 3 takes real
A
n
s w
e r :(Total 6 marks)
11
14.
1 Let f be the function f (x) = x arccos x + 2 x for 1 x 1 and g the function g (x) = cos 2xfor 1 x 1. (a) On the grid below, sketch the graph of f and of g. y 2 1 1 0 1 2 3 4 1 x
(b)
Write down the solution of the equation f (x) = g (x).
12
(c)
Write down the range of g.
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
13
15.
3x 4 , x + 2 x 2. The function f is defined as f (x) =(a) (b) Find an expression for f1
(x).1
Write down the domain of f
.
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
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16.
2x The function f is defined by f (x) = x + 6 for x b where b2
.
(a) (b)
12 2 x 2 . ( x 2 + 6) 2 Show that f (x) =
Hence find the smallest exact value of b for which the inverse function f your answer.
1
exists. Justify
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
15
17.
x2 1 2 The function f is defined for x 0 by f (x) = x + 1 .Find an expression for f (x). Working:1
Answer: .........................................................................(Total 6 marks)
18.
The set of all real numbers under addition is a group ( , +), and the set of all positive + real numbers under multiplication is a group ( , ). Let f denote the mapping of ( , +) to ( + x , ) given by f (x) = 3 . (a) (b) Show that f is an isomorphism of ( , +) onto ( Find an expression for f .(1) (Total 7 marks)1 +
+
, ).(6)
16
19.
The function f is defined for x > 2 by f (x) = ln x + ln (x 2) ln (x 4). x Express f (x) in the form ln x + a .
2
(a) (b)
Find an expression for f (x).
1
W
o
r k i n
g
:
A
n
s w
e r s :
( a ) ( b )(Total 6 marks)
17
20.
The diagram below shows the graph of y1 = f (x). The x-axis is a tangent to f (x) at x = m and f (x) crosses the x-axis at x = n. y y1 = f( x)
0
m
n
x
On the same diagram sketch the graph of y2 = f (x k), where 0 < k < n m and indicate the coordinates of the points of intersection of y2 with the x-axis. Working:
(Total 4 marks)
18
21.
For which values of the real number x is | x + k | = | x | + k, where k is a positive real number? Working:
Answer: ..............(Total 4 marks)
22.
Given that x > 0, find the solution of the following system of equations: 8x 3 = 3 y
9 xy y = x + 42
(Total 3 marks)
19
23.
The diagram below shows the graphs of y = x + 3x and y = g (x), where g (x) is a polynomial of degree 3. y y =3 2
3
2
x
3+
x
g ( A
)x
0 A
x
(a)
If g (2) = 0, g (0) = 4, g (2) = 0, and g (0) = (0) show that g (x) = x + 3x 4. The graph of y = x + 3x is reflected in the y-axis, then translated using the vector 1 1 to give the graph of y = h (x).3 2
3
2
(6)
(b)
Write h (x) in the form h (x) = ax + bx + cx + d.(5)
3
2
The graph of y = x + 3x 4 is obtained by applying a composition of two 3 2 transformations to the graph of y = x + 3x . (c) State the two transformations whose composition maps the graph of y = x + 3x onto 3 2 the graph of y = x + 3x 4 and also maps point A onto point A .3 2
3
2
(3) (Total 14 marks)
20
24.
5 2 Let f (x) = ln |x 3x |, 0.5 < x < 2, x a, x b; (a, b are values of x for which f (x) is not defined).
(a)
(i) Sketch the graph of f (x), indicating on your sketch the number of zeros of f (x). Show also the position of any asymptotes.(2)
(ii) (b) (c) (d)
Find all the zeros of f (x), (that is, solve f (x) = 0).(3)
Find the exact values of a and b.(3)
Find f (x), and indicate clearly where f (x) is not defined. Find the exact value of the x-coordinate of the local maximum of f (x), for 0 < x < 1.5. (You may assume that there is no point of inflexion.)
(3)
(3)
(e)
Write down the definite integral that represents the area of the region enclosed by f (x) and the x-axis. (Do not evaluate the integral.)(2) (Total 16 marks)
21
25.
The following graph is that part of the graph of y = f (x) for which f (x) 0. y 4 3 2 1 2 1 02
1
2
x
Sketch, on the axes provided below, the graph of y = f (x) for 2 x 2. y 4 3 2 1 2 1 0 1 2 3 4(Total 3 marks)
1
2
x
22
26.
(a)2
Sketch and label the curves
1 y = x for 2 x 2, and y = 2 ln x for 0 < x 2.(b) (c) Find the x-coordinate of P, the point of intersection of the two curves.
(2)
(2)
If the tangents to the curves at P meet the y-axis at Q and R, calculate the area of the triangle PQR.(6)
(d)
Prove that the two tangents at the points where x = a, a > 0, on each curve are always perpendicular.(4) (Total 14 marks)
23
27.
(a)
a + b sin x Let y = b + a sin x , where 0 < a < b.(b 2 + a 2 ) cos x dy 2 Show that dx = (b + a sin x) .(4)
(i) (ii)
Find the maximum and minimum values of y.(4)
(iii)
a + b sin x Show that the graph of y = b + a sin x , 0 < a < b cannot have a vertical asymptote.(2)
(b)
For the graph of (i) (ii) (iii)
y = 4 + 5 sin x 5 + 4 sin x for 0 x 2 ,
write down the y-intercept; find the x-intercepts m and n, (where m < n) correct to four significant figures; sketch the graph.(5)
(c)
y = 4 + 5 sin x 5 + 4 sin x and the x-axis from x = 0 to x = n is The area enclosed by the graph of denoted by A. Write down, but do not evaluate, an expression for the area A.(2) (Total 17 marks)
24
28.
The diagram shows a sketch of part of the graph of f (x) = x and a sketch of part of the graph of 2 g (x) = x + 6x 13 y
2
y=
f(
x)
x
y =(
g )
x
(a)
Write down the coordinates of the maximum point of y = g (x).
25
The graph of y = g (x) can be obtained from the graph of y = f (x) by first reflecting the graph of y = f (x), then translating the graph of y = f (x). (b) Describe fully each of these transformations, which together map the graph of y = f (x) onto the graph of y = g (x).
Working:
Answers: (a) .................................................................. (b) .................................................................. ..................................................................(Total 3 marks)
26
29.
The diagram shows the graph of the functions y1 and y2. y 2 0 2 y2
x
y1
y1 On the same axes sketch the graph of y 2 . Indicate clearly where the x-intercepts and asymptotes occur.Working:
(Total 3 marks)
30.
Let (a)
f ( x ) = x 3 ( x 2 1) 2 , 1.4 x 1.4 Sketch the graph of f (x). (An exact scale diagram is not required.) On your graph indicate the approximate position of (i) (ii) (iii) each zero; each maximum point; each minimum point.(4)
27
(b) (ii)
(i)
Find f (x), clearly stating its domain.
Find the x-coordinates of the maximum and minimum points of f (x), for 1 < x < 1.(7)
(c)
Find the x-coordinate of the point of inflexion of f (x), where x > 0, giving your answer correct to four decimal places.(2) (Total 13 marks)
31.
The line segment [AB] has length l, gradient m, (0 < m < 1), and passes through the point (0, 1). It meets the x-axis at A and the line y = x at B, as shown in the diagram. y y= B ( 0 A , 1 O ) x x
(a)
Find the coordinates of A and B in terms of m.(4)
l2 =
(b)
Show that
m2 +1 . m 2 (1 m) 2(3)
(c)
, x 2 (1 x) 2 for x 0, x 1, indicating any asymptotes and the Sketch the graph of coordinates of any maximum or minimum points.(4)
y=
x 2 +1
(d)
Find the value of m for which l is a minimum, and find this minimum value of l.(2) (Total 13 marks)
28
32.
Find the set of values of x for which (e 2) (e 3) 2e . Working:
x
x
x
Answer: ..........................................................................(Total 6 marks)
33.
The graph of the function f (x) = 2x 3x + x + 1 is translated to its image, g (x), by the vector 1 1 . Write g (x) in the form g (x) = ax3 + bx2 +cx + d. Working:
3
2
Answer: ..........................................................................(Total 6 marks)
29
34.
x 2 5x 4 2 Find the equations of all the asymptotes of the graph of y = x 5 x + 4 . Working:
Answer: .......................................................................... ..........................................................................(Total 6 marks)
35.
(a)
On the same axes sketch the graphs of the functions, f (x) and g (x), where f (x) = 4 (1 x) , for 2 x 4, g (x) = ln (x + 3) 2, for 3 x 5.(2)2
(b) (ii) (c) (d)
(i)
Write down the equation of any vertical asymptotes.(3)
State the x-intercept and y-intercept of g (x).
Find the values of x for which f (x) = g (x).(2)
Let A be the region where f (x) g (x) and x 0. (i) (ii) (iii) On your graph shade the region A. Write down an integral that represents the area of A. Evaluate this integral.(4)
(e)
In the region A find the maximum vertical distance between f (x) and g (x).(3) (Total 14 marks)
30
36.
The function f is given by f (x) = 2 x e . Write down (a) (b) the maximum value of f (x); the two roots of the equation f (x) = 0.
2
x
Working:
Answers: (a) .................................................................. (b) ..................................................................(Total 6 marks)
31
37.
The diagram shows the graph of f (x).
(a)
1 , On the same diagram, sketch the graph of f ( x) indicating clearly any asymptotes.y
2
1
2
1
0 1
1
2
x
2
(b)
On the diagram write down the coordinates of the local maximum point, the local 1 . f ( x) minimum point, the x-intercepts and the y-intercept of
Working:
(Total 6 marks)
32
38.
x 3 arcsin arccos 4 5 , for 4 x 4. Let f (x) = sin (a) On the grid below, sketch the graph of f (x). y 2
1
5
4
3
2
1 0
1
2
3
4
5 x
1
(b)
2
On the sketch, clearly indicate the coordinates of the x-intercept, the y-intercept, the minimum point and the endpoints of the curve of f (x).
(c)
1 Solve f (x) = 2 .
Working:
Answer: (c) ..................................................................(Total 6 marks)
33
39.
For 3 x 3, find the coordinates of the points of intersection of the curves y = x sin x and x + 3y = 1. Working:
Answer: .........................................................................(Total 6 marks)
40.
k Let f (x) = x k , x k, k > 0(a) On the diagram below, sketch the graph of f. Label clearly any points of intersection with the axes, and any asymptotes. y
k
x
34
(b)
1 On the diagram below, sketch the graph of f . Label clearly any points of intersection with the axes.y
k
x
Working:
(Total 6 marks)
35
41.
Consider the equation e = cos 2x, for 0 x 2. (a) (b) How many solutions are there to this equation? Find the solution closest to 2, giving your answer to four decimal places.
x
Working:
Answers: (a) .................................................................. (b) ..................................................................(Total 6 marks)
36
42.
The following diagram shows the lines x 2y 4 = 0, x + y = 5 and the point P(1, 1). A line is drawn from P to intersect with x 2y 4 = 0 at Q, and with x + y = 5 at R, so that P is the midpoint of [QR]. y 1 8 6 4 2 1 0 8 6 4 2 Find the exact coordinates of Q and of R. Working: 1 0 2 4 6 8 0 P ( 1 2 , 4 1 ) 6 8 1 0x 0
Answer: .........................................................................(Total 6 marks)
37
43.
Solve the equation
e 2x
1 x + 2 = 2.
W
o
r k i n
g
:
A
n
s w
e r :
(Total 6 marks)
38
44.
2 2 The graph of y = 2x + 4x +7 is translated using the vector 1 . Find the equation of the translated graph, giving your answer in the form y = ax + bx +c.
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
39
45.
Each of the diagrams below shows the graph of a function f. Sketch on the given axes the graph of (a)
f (x )
; y
x
(b)
1 f ( x) .y
x
(Total 6 marks)
40
46.
x . The graph of y = cos x is transformed into the graph of y = 8 2 cos 6Find a sequence of simple geometric transformations that does this. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
41
47.
The diagrams below show the graph of y = f (x) which passes through the points A, B, C and D. Sketch, indicating clearly the images of A, B, C and D, the graphs of (a) y = f (x 4);
(2)
(b)
y = f ( 3x).
(4) (Total 6 marks)
42
48.
Determine the values of x that satisfy the following inequalities
x +2(a)
x 3
< 4;(3)
(b)
xe x 1. ( x 2 1)
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(3) (Total 6 marks)
43
49.
The function f is defined by f (x) = cosec x + tan 2x.
(a)
Sketch the graph of f for Hence state (i) (ii) (iii) the x-intercepts;
x . 2 2
the equations of the asymptotes; the coordinates of the maximum and minimum points.(8)
(b)
Show that the roots of f (x) = 0 satisfy the equation 3 2 2 cos x 2 cos x 2 cos x + 1 = 0.(5)
(c)
Show that the x-coordinates of the maximum and minimum points on the 5 3 2 curve satisfy the equation 4 cos x 4 cos x + 2 cos x + cos x 2 = 0.(8)
(d)
Show that f ( x) + f ( + x) = 0.(4) (Total 25 marks)
44
50.
(a) Sketch the curve f (x) = | 1 + 3 sin (2x)| , for 0 x . Write down on the graph the values of the x and y intercepts.
(4)
(b)
By adding one suitable line to your sketch, find the number of solutions to the equation f (x) = ( x).
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(2) (Total 6 marks)
45
51.
A system of equations is given by cos x + cos y = 1.2 sin x + sin y = 1.4. (a) (b) For each equation express y in terms of x.(2)
Hence solve the system for 0 < x < , 0 < y < .
(4)
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
46
52.
The graph of y = f (x) for 2 x 8 is shown.
1 , f ( x ) clearly showing any asymptotes and On the set of axes provided, sketch the graph of y =indicating the coordinates of any local maxima or minima.
(Total 5 marks)
47
53.
Find the set of values of x for which
0.1x 2 2 x + 3 < log 10 x.
.............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(Total 6 marks)
54.
Find the values of x for which 5 3x x + 1 . Working:
Answer: ..........................................................................(Total 3 marks)
48
55.
3 2 Solve the inequality x 4 + x < 0. Working:
Answer: .......................................................................... ..........................................................................(Total 6 marks)
56.
Solve the inequality 2 + 1 x 2x . Working:
Answer: .........................................................................(Total 6 marks)
49
57.
x+4 x2 Let f (x) = x + 1 , x 1 and g (x) = x 4 , x 4.Find the set of values of x such that f (x) g (x). Working:
Answer: .........................................................................(Total 6 marks)
58.
Solve the inequality
x+9 x9 2Working:
Answer: .........................................................................(Total 6 marks)
50
59.
x+4 x2 Let f (x) = x + 1 , x 1 and g (x) = x 4 , x 4. Find the set of values of x such that f (x) g (x)................................................................................................................................................ ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ...............................................................................................................................................(Total 6 marks)
51
60.
x 2 + 5x + 5 x+2 Let f (x) = , x 2.
(a) (b)
Find f (x). Solve f (x) > 2. o r k i n g :
W
A
n
s w
e r s :
( a ) ( b )(Total 6 marks)
52