Question

Evaluate f(x+h)-f(x)/h and simplify if f(x)=x^2-2x ...?

Answer 1

`(f(x+h)-f(x))/(h)= \\ = ((x+h) ^(2)-2(x+h)-( x^(2) -2x) )/(h)= \\ = ( x^(2) +2hx+ h^(2)-2x-2h+2x )/(h)= \\ = (2hx+ h^(2)-2h )/(h)= \\ = (h(2x+h-2))/(h)=`
= 2 x + h - 2