Question

Разложите на множители:
а)3x^2y^3-3x^4y^2+9x^2y;
б)2х-x^2+y^2+2y

Answer 1

$3x^2y^3-3x^4y^2+9x^2y=3x^2y*y^2-3x^2y*x^2y+3x^2y*3=$
$3x^2y(y^2-x^2y+3)$
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$2x-x^2+y^2+2y=(2x-2y)-(x^2-y^2)=$
$2(x-y)-(x-y)(x+y)=(2-(x+y))(x-y)=$
$(2-x-y)(x-y)$