Definition+of+the+derivative+at+a+point+x+=+a

Use the example from the definition of the derivative, f'(x)=2x. To find the derivative at a specific point x=a, plus in your a value into the derivative for x.

Ex: x=3 f'(x)=2x f'(3)=2(3) f'(3)=6 (the slope at the point x=a is 6)