9 Phân tích đa thức sau thành nhân tử:
a) 9xy^2-18x^2y ; b) 6x^2-2y ; c)7x(x-y)-14y(y-x)
d)7-x^2 ; e) 16+8x+x^2 ; f)1-27x^3
g) x^3-9x^2+27x-27 ; h) (x+2y)^2-16y^2 ; i) x^3-64y^3
Giups mình với các bạn ơi!
@Nguyễn Huy Tú@DƯƠNG PHAN KHÁNH DƯƠNG@Nguyễn Thanh Hằng@Phùng Khánh Linh
\(a.9xy^2-18x^2y=9xy\left(y-2x\right)\)
\(b.6x^2-2y=2\left(3x^2-y\right)\)
\(c.7x\left(x-y\right)-14y\left(y-x\right)=7x\left(x-y\right)+14y\left(x-y\right)=7\left(x-y\right)\left(x+2y\right)\)
\(d.7-x^2=\left(\sqrt{7}-x\right)\left(\sqrt{7}+x\right)\)
\(e.16+8x+x^2=\left(x+4\right)^2=\left(x+4\right)\left(x+4\right)\)
\(f.1-27x^3=\left(1-3x\right)\left(1+3x+9x^2\right)\)
\(g.x^3-9x^2+27x-27=\left(x-3\right)^3=\left(x-3\right)\left(x-3\right)\left(x-3\right)\)
\(h.\left(x+2y\right)^2-16y^2=\left(x+2y-4y\right)\left(x+2y+4y\right)=\left(x-2y\right)\left(x+6y\right)\)
\(i.x^3-64y^3=\left(x-4y\right)\left(x^2+4xy+16y^2\right)\)
