For the function f(x)=x^2-x find f(x+h)-f(x)\h

Answer 1

f(x) = x² - x

f(x+h) = (x+h)² - (x+h) = x² + 2xh + h² -x - h

f(x+h) - f(x) = x² + 2xh + h² -x - h - (x² - x) = 2xh + h² - h

(f(x+h) - f(x))/h = (2xh + h² - h)/h = 2x + h - 1