Question

e(x)=(x+5)ttul la a doua-(x-5)totul la a doua
x apartine lui r
e(5)=?

Answer 1

     
$E(x)=(x+5)^2-(x-5)^2 \;\;\;\;x \in R \\ \\ E(5) = (5+5)^2-(5-5)^2=10^2-0^2 = 100-0=\boxed{100}$

Answer 2

E(5) =(5²+10ori5+5²) -(5²-10 ori 5+5²)= 100-0=100