Question

sendo f(x) x²+2x

A) f (x+h) - f(x) / h

Answer 1

$\boxed{f(x)=x^2+2x}\\ \\ \frac{f(x+h)-f(x)}{h}=\frac{(x+h)^2+2(x+h)-x^2-2x}{h}=\frac{x^2+2hx+h^2+2x+2h-x^2-2x}{h}=\\ \\ \frac{2hx+h^2+2h}{h}=2x+h+2$