Question

Se considera expresia E(x) =(x²-1):(x+x²-4/2x-4 * 2x+4/x²+4x+4).

Answer 1

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