where f'(x) = gradient (or slope) of f(x) at x = x.

Prove that:
d/dx(x^2) = 2x

without using calculus.

OK

So am I correct in assuming that this "proof" only applies to f(x) = x² because its graph is a parabola. And that we can use the definition of a parabola to find the line which is tangent to the parabola at any given point?

Posted by TomM on 2002-08-01 05:41:19