a) x3 - 6x2 +9x =x.(x2-6x+9)=x.(x-3)2
b) x2-2x-4y2-4y = x2 - 4y2 - 2x-4y = (x-2y)(x+2y) -2(x+2y)
=(x+2y)(x-2y-2)
a)x3-6x2+9x
=x(x2-6x+9)
=x(x2-2.x.3+32)
=x(x-3)2
b) x2-2x-4y2-4y
=(x2-4y2)-(2x+4y)
=(x-2y)(x+2y)-2(x+2y)
=(x+2y)(x-2y-2)
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