分解因式:3a^2-9ab ,4x^3y+x^2y^2+2xy^3 ,4x^4-4x^3+6x^2
问题描述：
分解因式:3a^2-9ab ,4x^3y+x^2y^2+2xy^3 ,4x^4-4x^3+6x^2
答
3a^2-9ab=3a(a-3b)
4x^3y+x^2y^2+2xy^3 =xy(4x^2+xy+2y^2)
4x^4-4x^3+6x^2=2x^2(2x^2-2x+3)
答
3a(a-3b)
xy(4x^2+xy+2y^2)
2x^2(2x^2-2x+3)