cum se rezolva
[tex](x {}^{2} - x + 2) { }^{2} [/tex]


Răspuns :

Folosim formula de calcul prescurtat

(a+b+c)²=a²+b²+c²+2ab+2bc+2ac

(x²-x+2)² = (x²)²+(-x)²+2²+2x²(-x)+2(-x)2+2x²2 =

x⁴+x²+4-2x³-4x+4x² = x⁴-2x³+5x²-4x+4

(x²-x+2)²=

(x²-x+2)(x²-x+2)=

x²(x²-x+2)-x(x²-x+2)+2(x²-x+2)=

x⁴-x³+2x²-x³+x²-2x+2x²-2x+4=

x⁴+(-x³-x³)+(2x²+x²+2x²)+(-2x-2x)+4=

x⁴-2x³+5x²-4x+4