Firstly, I'm not sure which section this goes in (so please don't infract me for it )

a) Differentiate from first principles $\displaystyle y=x^2+2 $

I get $\displaystyle 2x $

b) Find the gradient of the secant through the points. A(1,3) and B(3,11)

What is a secant?

c) Find the equation of the tangent to the curve at the point A

How would I go about doing this?