Follow the steps in Ex. 91.2 to prove the following on your paper. Does the proof work out for f'(x)- g'(x), too? Type yes or no. Correct spelling required. Help: Lecture 91, Ex. 91.2 d 291 Use the rule that lim (f-g)x = lim f(x) - lim g(x), to prove that dx (fg)(x)=f'(x)