Answers 461
8 f¡^1 (x)=^1
x
andf(x)=^1
x
) f=f¡^1
) fis a self-inverse function
9af¡^1 (x)=2x+2
bi(f±f¡^1 )(x)=x ii (f¡^1 ±f)(x)=x
10 a 10
bf¡^1 (x)=
x¡ 5
2
and f¡^1 (¡3) =¡ 4
g¡^1 (x)=8¡ 2 x and g¡^1 (6) =¡ 4
) f¡^1 (¡3)¡g¡^1 (6) = 0
cx=3
11 a i 25 ii 16 bx=1
12 aIs not b Is c Is dIs eIs f Is not
13 (f¡^1 ±g¡^1 )(x)=
x+3
8
and (g±f)¡^1 (x)=
x+3
8
REVIEW SET 2A
1afunction b function c not a function dfunction
2 a=¡ 6 ,b=13
3ax=¡ 2 or 12 b x=¡ 5 or 1
4a 10 bx^2 ¡x¡ 2
5a iDomain isfx:x>¡ 3 g, Range isfy:y> 2 g
ii function is one-one
biDomain isfx:x 2 Rg, Range isfy:y>¡ 5 g
ii function is not one-one
ciDomain isfx:x 2 Rg,
Range isfy:y=¡ 3 ory=1g
ii function is not one-one
6a b
7
8a b
9a 2 x^2 +1 b 4 x^2 ¡ 12 x+11
10 a b
cThe function does not have an inverse.
11 af¡^1 (x)=x¡^2
4
bf¡^1 (x)=^3 ¡^4 x
5
12 a f(¡3) = (¡3)^2 =9
g(¡^43 )=1¡6(¡^43 )=9
b 169 c x=¡ 4
13 (f¡^1 ±h¡^1 )(x)=(h±f)¡^1 (x)=x¡ 2
REVIEW SET 2B
1anot a function b function, one-one
cfunction, not one-one
2a 12 bx=§ 1
3ax=¡ 5 or 6 b x=1or 3
4a b
5a 10 ¡ 6 x b 9 x¡ 14 c ¡ 23
6 fy:3 6 y 67 g 7
8a i 1 ¡ 10 x ii 5 ¡ 10 x bx=¡^35
9 a=1, b=¡ 6 , c=5
10 a c
bThe function does not have an inverse.
11 af¡^1 (x)=
7 ¡x
4
bf¡^1 (x)=
5 x¡ 3
2
12 (f¡^1 ±h¡^1 )(x)=(h±f)¡^1 (x)=
4 x+6
15
1316
EXERCISE 3A.1
1ax=0,¡^74 bx=0,¡^13 c x=0,^73
dx=0,^112 ex=0,^83 f x=0,^32
gx=3, 2 hx=4,¡ 2 i x=3, 7
j x=3 kx=¡ 4 , 3 l x=¡ 11 , 3
2ax=^23 bx=¡^12 , 7 c x=¡^23 , 6
dx=^13 ,¡ 2 ex=^32 , 1 f x=¡^23 ,¡ 2
gx=¡^23 , 4 hx=^12 ,¡^32 i x=¡^14 , 3
j x=¡^34 ,^53 kx=^17 ,¡ 1 l x=¡ 2 ,^2815
3ax=2, 5 bx=¡ 3 , 2 c x=0,¡^32
dx=1, 2 ex=^12 ,¡ 1 f x=3
- We 4
-+-x
-2 3
--+x
y
x
2
2
y=x¡¡
f-1(x)
f(x)
OO
y
x
2
5
25
f-1(x) y=x¡¡
f(x)
O
y
O 3 x
1
y= 1- x||Qe
1
+-x
y
x
-2
-2
2
2
f-1(x)
f(x)
y=x¡¡
O
y
x
f(x)^3
f (x)-1
3
y=x
O
-2 3
--+x
y
O x
1
Qw
y= 2x-1||
y
x
y = (x)¦
O
y = f(x)||
y
x
y = (x)¡¦
O
y = f(x)||
cyan magenta yellow black
(^05255075950525507595)
100 100
(^05255075950525507595)
100 100 IB HL OPT
Sets Relations Groups
Y:\HAESE\CAM4037\CamAdd_AN\461CamAdd_AN.cdr Tuesday, 8 April 2014 8:21:43 AM BRIAN