(y²+3y)²-(2y+6)²

(y²+3y)²-(2y+6)²
(y²+3y)²-(2y+6)²

(y²+3y)²-(2y+6)²
(y²+3y)²-(2y+6)²
=y^4+6y³+9y²-4y²-24y-36
=y^4+6y³+5y²-24y-36

(y²+3y)²-(2y+6)²
=[(y²+3y)+(2y+6)][(y²+3y)-(2y+6)]
=(y²+5y+6)(y²+y-6)
=(y+2)(y+3)(y-2)(y+3)
=(y+2)(y-2)(y+3)²
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