Question

F (x) = 4x + 7. Find the inverse of f(x).

O A. f-1 (x) = -74
OB. f-'(x) = 7 - 4x
O c. f-1(x) = 11
O D. f ? (x) = 4x – 7
Anybody please ? I suck at math !

Answer 1

C. f(x) = x - 7 all over 4

Explanation:

NB: Let f(x) = y

Exchange X and Y

Make y the subject

f(x) = 4x + 7

y = 4x + 7

x = 4y + 7

x - 7 = 4y

x - 7 all over 4 = 4 ÷ 4

y = x - 7 all over 4