If f(x) = sqrt(3x)

then f'(x) = ?

and f' (4) = ?

I have done this problem over and over again and the result remains the same, incorrect. Here is what I did:

d/dx[sqrt(3x)] =

d/dx[sqrt(3)] d/dx[x^1/2] =

0 + 1/2x^-1/2

I also tried 3^1/2 + 1/2x^-1/2 = 1/2 +1/2/sqrt(x)

I must not using the rules correctly and I read them over again and I am not getting it. Please explain the error of my ways.

Thankx,

Keith