提公因式法同步练习题及答案.doc

1.2提公因式法一、请你填一填(1)单项式-12x12y3与8x10y6的公因式是_(2)-xy2(xy)3x(xy)2的公因式是_(3)把4ab2-2ab8a分解因式得_(4)5(m-n)4-(n-m)5可以写成_与_的乘积二、认真选一选(1)多项式8xmyn-1-12x3myn的公因式是()Axmyn Bxmyn-1 C4xmyn D4xmyn-1(2)把多项式-4a34a2-16a分解因式()A-a(4a2-4a16)Ba(-4a24a-16)C-4(a3-a24a)D-4a(a2-a4)Ac-b5acBcb-5acCc-bacDcb-ac(4)用提取公因式法分解因式正确的是()A12abc-9a2b23abc(4-3ab)B3x2y-3xy6y3y(x2-x2y)C-a2ab-ac-a(a-bc)Dx2y5xy-yy(x25x)三、请分解因式(1)x(x-y)-y(y-x)(2)-12x312x2y-3xy2(3)(xy)2mxmy(4)a(x-a)(xy)2-b(x-a)2(xy)四、好好想一想1求满足下列等式的x的值5x2-15x05x(x-2)-4(2-x)02若a-5，abc-5.2，求代数式a2(-b-c)-3.2a(cb)的值参考答案一、(1)4x10y3 (2)x(xy)2 (3)2a(2b2-b4)(4)(m-n)4 (5m-n)二、(1)D (2)D (3)A (4)C三、(1)x(x-y)-y(y-x)(x-y)(xy)(2)-12x312x2y-3xy2-3x(4x2-4xyy2)-3x(2x-y)2(3)(xy)2mxmy(xy)2m(xy)(xy)(xym)(4)a(x-a)(xy)2-b(x-a)2(xy)(x-a)(xy)a(xy)-b(x-a)(x-a)(xy)(axay-bxab)四、1.5x(x-3)0，则5x0，x-30，x0或x3(x-2)(5x4)0，则x-20或5x40，x2或x-2a-5，abc-5.2，bc-0.2a2(-b-c)-3.2a(cb)-a2(bc)-3.2a(bc)(bc)(-a2-3.2a)-a(bc)(a3.2)5(-0.2)(-1.8)1.8