descompuneti in factori: -5x la puterea 2 -x+4

Răspuns :

-5x^2-5x+4x+4=-5x(x+1)+4(x+1)=(x+1)(-5x+4)
[tex]-5x^2-x+4=-4x^2+4-x^2-x=-4(x^2-1)-x(x+1)[/tex]
=[tex]-4(x+1)(x-1)-x(x+1)=(x+1)(-4(x-1)-x)=[/tex]
=[tex](x+1)(-5x+4)[/tex]