Which function is the best inverse of f (x) = x2-9

The inverse is sqrt (x+9)

Step-by-step explanation:

f (x) = x^2-9

To find the inverse of the function, we interchange x and y and solve for y

y = x^2 - 9

x = y^2 - 9

Add 9 to each side

x+9 = y^2 - 9+9

x+9 = y^2

Take the square root of each side

sqrt (x+9) = sqrt (y^2)

sqrt (x+9) = y

f^-1 (x) = sqrt (x+9)