If g(x) = x^2 + 2x with x ≥ −1, find g^−1(24).

Question

Please help. I need the answer

Answer 1

y = x² + 2x

Reverse the roles of x and y

x = y² + 2y

Solve for y

y = (-2+ sqrt(4 + 4x))/2

You should graph these two functions and see that for x ≥ -1, they are symmetric with respect to y = x.

Substitute x = 24 in the expression for g^-1 to see the the value is 4