Question

Calculati,utilizand formulele de calcul prescurtata:
x(x-2)+2(x-1)²+(x-1)(x+1)-4(x²-1)
As vrea rezolvaarea completa, va rog!

Answer 1

$x^2-2x+2(x^2-2x+1)+x^2-1-4x^2+4= \\ =x^2-2x+2x^2-4x+2+x^2-1-4x^2+4= \\ =4x^2-4x^2-6x+6-1= \\ = -6x+5$

Answer 2

[tex]x(x-2)= x^{2} -2x\\ 2(x-1)^{2}=2(x^{2}-2x+1)=2x^{2}-4x+2\\ (x-1)(x+1)=x^{2}-1\\ -4(x^{2}-1)=-4x^{2}+4\\ E(x)=x^{2}-2x+2x^{2}-4x+2+x^{2}-1-4x^{2}+4=-6x+5[/tex]