Multiple Choice Questions
Unit G4
Functions
For each of these questions, choose the option that is TRUE.
1
If f(x) = 3x2 + 4x − 5, then f(−2) =
- (A)−49
- (B)−1
- (C)9
- (D)23
2
1 → 3
2 → 5
3 → 7
4 → 9
Which of the following could describe the mapping above?
- (A)f : x → x + 3
- (B)f : x → 2x + 1
- (C)f : x → x2 + 1
- (D)f : x → 2x2 − 3
3
If f : x → x2 + 1, then f(−3) is
- (A)10
- (B)7
- (C)−5
- (D)−8
4
f(4) = −2, so f−1(−2) =
- (A)−4
- (B)−
- (C)
- (D)4
5
If f(x) = x + 1 and g(x) = x2 , then gf(2) =
- (A)3
- (B)4
- (C)5
- (D)9
6
f(x) = 2x − 1, so f−1(3) =
- (A)1
- (B)2
- (C)3
- (D)4
7
f(x) = , ff−1(1) =
- (A)2
- (B)1
- (C)
- (D)0
Total: -
of marks