因式分解

显示全部楼层 · 2009-5-30 21:25:29

（1）-x^2y^2+z^2=(z-xy)(z+xy)（2）a^b-2ab+ab^2=a(a^(b-1)-2b+b^2)是不是有点错啊(3)3ax^2+6axy+3ay^2=3a(x^2+2xy+y^2)=3a(x+y)^2(4)(1/4)x^2-xy+y^2=(x/2-y)^2(5)x(x+2)-2(x+2)-12=x^2+2x-2x-4-12=x^2-16=(x+4)(x-4)(6)a^4-16=(a^2+4)(a^2-4)=(a^2+4)(a+2)(a-2)(7)x(x+2)(x-2)-4x^2+8x=x((x+2)(x-2)-4x+8)=x(x^2-4-4x+8)=...

千问 · 2009-5-30 21:25:29

（1）-x^2y^2+z^2=z^2-x^2y^2=(z-xy)(z+xy)（2）a^b-2ab+ab^2=ab(a-2+b)(3)3ax^2+6axy+3ay^2=3a(x^2+2xy+y^2)=3a(x+2y)^2(4)(1/4)x^2-xy+y^2=1/4(x^2-4xy+4y^2)=1/4(...

千问 · 2009-5-30 21:25:29

1.原式=(z-xy)(z+xy)2.原式=ab(a+b-2)3.原式=3a(x^2-2xy+y^2)=3a(x+y)^24.原式=(1/2x-y)^25.原式=x^2+2x-2x-4-12=x^2-4^2=(x-4)(x+4)6.原式=(a^2+4)(a^2-4)=(a^2+4)(a-2)(a+2)7.原式=x(x+2)^2...

千问 · 2009-5-30 21:25:29

1.-x^2y^2+z^2 =z^2-(xy)^2=(z+xy)(z-xy)2.a^b-2ab+ab^2好像有点儿问题，应该是：a^2b-2ab+ab^2=(a^2b-ab)+(ab^2-ab)=ab(a-1)+ab(b-1)=ab(a+b-2)3.3ax^2+6axy+3ay^2 =3a(x^2+2xy+...