Question

E(x) =(1+x)(1-x)+(x+2)totul la a 2a - 2(x+2) ,unde x e R
Aflati nr real a pt care E(a) = -2
Cine ma ajuta ?

Answer 1

[tex]E(x)=(1+x)(1-x)+(x+2)^2-2(x+2),x \in \mathbb{R}\\ E(a)=2:\\ (1+a)(1-a)+(a+2)^2-2(a+2)=2\\ 1-a^2+a^2+4a+4-2a-4=2\\ 2a=1\\ \boxed{\bold{a=\frac{1}{2}}}\\ [/tex]