Question 1009861
Use the definition of the derivative to find f ′(x) if
f(x)=x^2+x
f'(x) = 2x + 1
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f(x)=  1/(x-1) = (x-1)^(-1)
f'(x) = -1(x-1)^(-2)
= {{{-1/(x-1)^2}}}