I don't know if this is pre-university or university level calculus,

but it would be greatly appreciated if someone could explain the

following problem to me:

Problem:

Let F(x) = x/6

a. Take the derivative of F(x) with respect to x to find a new function f(x).

I think this should be x^{-6}, am I correct?

b. Suppose f(x) is to serve as a probability model; it then should have a surface area

equal to 1 and all its values should be positive.

Suppose also that the domain starts at zero.

What is the upper boundary of this domain?

Thanks in advance