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**vaironxxrd** For the function f defined by f(x) = $\displaystyle 2x^2-3x$

Evaluate: $\displaystyle \frac{f(x+h)-f(x)}{h}$

I'm solving the problem using a book which actually gives me step-by-step instructions. Thing is I have a confusion with the following distribution, and the book is not showing the distribution step.

$\displaystyle \frac{f(x+h)-f(x)}{h}=\frac{[2(x+h)^2 -3(x+h)]-[2x^2-3x]}{h}$

When I do this step I receive the following:

$\displaystyle \frac{2x^2+2h^2-3x-3h-2x^2-3x}{h}$

What the book gives

$\displaystyle \frac{2(x^2+2xh+h^2)-3x-3h-2x^2+3x}{h}$

What am I doing wrong? Everything?