Question

Descompune :x la a3a-(2x-y) toata paranteza la a3a va roog

Answer 1

Folosim formula:
$a^{3} - b^{3} = ( a-b )*( a^{2} + a*b + b^{2} )$

$x^{3} - (2x-y)^{3} =$
$= [ x - (2x-y)]*( x^{2} + x*(2x-y)+(2x-y)^{2} ]=$
$= ( x - 2x+y)*( x^{2} + 2 x^{2} -x*y + 4*x^{2}-4*x*y+ y^{2} )=$
$= ( y-x)*( 7* x^{2} -5*x*y + y^{2} )$

Sper ca nu am gresit la calcule. Daca da, voi corecta.