Answer:
f^-1 (x) = ±sqrt(x-16)
Explanation:
To find the inverse of a function, exchange x and y and solve for y
y=x^2+16
Exchange x and y
x = y^2 +16
Then solve for y
Subtract 16 from each side
x-16 = y^2 +16-16
x-16 = y^2
Take the square root of each side
±sqrt(x-16) = sqrt(y^2)
±sqrt(x-16) = y
The inverse
f^-1 (x) = ±sqrt(x-16)