Another question from me.

The curve C has equation $\displaystyle y=x^2(x-6) + \frac{4}{x}, x>0$.

The Points P and Q lie on C and have x-coordinates 1 and 2 respectively.

a) Show that the length of PQ is $\displaystyle \sqrt 170$.

b) Show that the tangents to C at P and Q are parallel.

c) Find an equation for the noram to C at p giving your answer in the form $\displaystyle ax +by+c = 0$

No idea where to start with this equation the $\displaystyle + \frac{4}{x}$ on the end really confuses me too, haven't seen that before.