Hi, after a long break I've decided to look at my math hw since I go back to school tomorrow. Well, I don't understand the first problem so hopefully if I can get help with this one I can understand the rest.

1. (noncalculator) The minimum value of f(x) = x^4 - 4x^3 + k is 7. Determine the value of k

I know how to find min and max values, but this is different so all help is appreciated.

Thanks