Determine f^-1(x) for f(x)= 3 times the square root of x-3.

Question

psymon · Answer

$$3\sqrt{x-3}$$
correct?

anonymous · Answer

yes! sorry, I didn't know how to do that.

psymon · Answer

You can click the equation button below the chat box thingy xD 
But alright, so if you need f inverse, then you need to switch x and y in your equation and then resolve for y. So basically you have:
$$y = 3\sqrt{x-3}$$ which becomes
$$x = 3\sqrt{y-3}$$
Do you know how to solve for y from here?

anonymous · Answer

I was pretty sure I did. I thought that since it's a cube root, you raise the whole function to the power of 3 to get rid of the cube root so it'd be x=(y-3)^3 


right?