how to differentiate (x^3) - 2 using [f(x+h)-f(x)]/h

2 answers

just plug and chug
f(x+h)-f(x) = (x+h)^3 - 2 - (x^3-2) = 3hx^2 + 3h^2 x + h^3
Now divide by h and you have
3x^2 + 3hx + h^2
take the limit and you wind up with
3x^2
alright thanks