Given the function f(x) = 4(x+3) − 5, solve for the inverse function when x = 3

inverse-function

#1

Given the function f(x) = 4(x+3) − 5, solve for the inverse function when x = 3

Answer:

Well,
we have :
y = f(x)
y = 4x + 12 - 5
y = 4x + 7
4x = y - 7
so the inverse function f^-1 is :
x = f^-1(y) = y/4 - 7/4
therefore :
f^-1(y) = y/4 - 7/4
and for y = 3 we get :
f^-1(3) = 3/4 - 7/4

f^-1(3) = -1 <— last answer