4x4 - 9x2
= 4x2 . x2 - 9x2
= (4x2 - 9)x2
Ko chắc đâu bạn ak!
\(4x^4-9x^2\)
\(=\left(2x^2\right)^2-\left(3x\right)^2\)
\(=\left(2x^2-3x\right)\left(2x^2+3x\right)\)
25-a2+4ab-4b2
= 25-(a2 -4ab+4b2)=52-(a-2b)2 =(5-a+2b)(5+a-2b)
7x2-14xy2+7y4
=7(x2-2xy+y2)=7(x-y)2
X2+4x-y2+4
= (x2+4x+4)-y2=(x+2)2-y2=(x+2-y)(x+2+y)
4x4-9x2
=x2(4x2-9)=x2(2x-3)(2x+3)
2x3-8x2+8x =2x(x2-4x+4)=2x(x-2)2
6xy+5x-5y-3x2-3y2
=(-3x2-3y2+6xy)+5(x-y)=-3(x2-2xy+y2)+5(x-y)=-3(x-y)2+5(x-y)=(x-y)(5+3y-3x)