Let f (x) = ax + 4, if f ′ (1) = 2, then the value of a () A. 2B. -2C. 3D. -3

Because f (x) = ax + 4, f ′ (x) = a, from F ′ (1) = 2. So a = 2

RELATED INFORMATIONS

1. F (x) are respectively equal to: F (x) = ax + 1 x ≤ 2 F (x) = x ^ 2 x > 2 find a B
2. If f (x) = (AX + 1) (x + a) is an odd function, what is f (2) equal to
3. Let f (x) = x ^ 2-ax + 1, and | f (1) | be less than or equal to 1, find the range of A
4. If f (1-2x) = 1-x ^ 2 / x ^ 2 (x is not equal to 0), then f (1 / 2)=___
5. F (x) + F [(x-1) / x] = 2x, X is not equal to 0,1. Find f (x)
6. If f (x-1) = x ^ 2 + 4x-5, then f (x + 1) equals Such as the title
7. If f {2 ^ x} = 4x, then f {8} is equal to
8. Given the function f (x) = 14x4 − X3 + x2 + a (0 & lt; X ≤ 6); (1) find the monotone interval and the maximum value of the function; (2) when a is the value, the equation f (x) = 0 has three different real roots
9. If f (2x-1) = 4x ^ 2 + 4x + 2, what is f (x) equal to?
10. Given the function f (x + 2) = x & # 178; - x + 1, then f (x) is equal to
11. Given the function f (x) = 3, X ∈ R, then the value of F (3) is equal to
12. Given the function f (x) = 11-x, then f (3) = 0___ ．
13. If f (x) = x ^ 3-x ^ 2-x + 1, what is the maximum value of X on [- 1,1]?
14. Let f (x) = x (x + 1) (x + 2) (x + n), then f ′ (0)=______ ．
15. Let f (x) = A / x + A, and f (2) = 3 / 2, then f (1) is equal to
16. Given 2F (1 / x) + F (x) = x (x is not equal to 0), find f (x)
17. It is known that the function f (x) is equal to one part of X, X
18. If f (x) = x + (A / x-1) has a minimum value of 4 when x is greater than or equal to 3, then a =? Needs process, good + 100 points
19. If f (x) = - cos π x (x > 0) f (x + 1) + 1 (x ≤ 0), then the value of F (43) + F (- 43) is equal to______ ．
20. Let f (x) be an odd function on (- ∞, + ∞), f (x + 2) = - f (x). When 0 ≤ x ≤ 1, f (x) = x, then f (7.5) is equal to () A. 0.5B. -0.5C. 1.5D. -1.5