Question

We have `f:RR->RR,f(x)={(-x^2+9,x<0),(2x+9,x>=0):}`.Value of inverse of function in point `x=8`?

Answer 1

`-1/2`

Explanation:

You want to invert `g(x) = 2x + 9`
exchange `x and y`

`x = 2y + 9 => y = (x - 9)/2 = f^-1(x)`

`f^-1(8) = (8 - 9)/2`