Question

Given the function f(x) = 2x, find the value of f−1(16).

Answer 1

8.

First you must find the inverse of the function since that's what the f-1 means. You do this by switching the f(x) and the x and then solve for f(x).

f(x) = 2x - switch them
x = 2f(x) - now divide the 2 away
x/2 = f(x) - now put the 16 in for x to find f-1(16)
16/2 = f(x)
8 = f(x)

Answer 2

Hi there! The answer is 8.


`f(x) = 2x`
First we need to find the inverse function.


`y = 2x`
Switch places of the variables.


`x = 2y`
Divide both sides of the equation by 2.


`(1)/(2) x = y`
Switch sides.


`y = (1)/(2) x`
Now we've found our inverse function.


`f {}^( - 1) (x) = (1)/(2) x`
Plug in x = 16 into the formula.


`f {}^( - 1) (16) = (1)/(2) * 16 = 8`
Therefore, the answer is 8.
~ Hope this helps you!