提公因式法同步練習(xí)題及答案

1、1.2提公因式法、請(qǐng)你填一填(1) 單項(xiàng)式-12x12y22與8x10y6的公因式是.(2) - xy2(x + y)3+ x(x+ y)2的公因式是 . 把4ab-2ab+ 8a分解因式得 .5( m- n)-12 x + 12xy-3 xy-( n-m)5可以寫成與的乘積.二、認(rèn)真選一選(1)多項(xiàng)式 8xmyn-1-12x3myn的公因式是().m nm n-1A. x y B. x ym nC. 4x ym n-1D.4x y32把多項(xiàng)式-4 a + 4a-16 a分解因式()2A. -a(4a-4a+ 16)2B. a(-4 a + 4a-16)C. -4( a3- a2 + 4a)2

2、D. -4 a( a - a+ 4)(3) 如果多項(xiàng)式-扌誕£+的一因式是-ab,那么另一因式杲(A. c- b+ 5ac1D. c + b- acB. c + b-5 acC. c- b+ ac5(4)用提取公因式法分解因式正確的選項(xiàng)是()2 2A. 12abc-9a b = 3abc(4-3 ab)B. 3x2y-3xy+ 6y= 3y(x2- x+ 2y)2C. -a + ab-ac= -a(a-b+ c)2 2D. x y+ 5xy- y= y( x + 5x)三、請(qǐng)分解因式(1) x( x- y)- y( y- x)2(3)( xy) mxmy22(4) a( x- a)(

3、 xy) 2 .假設(shè) a= -5 , a+ b+ c= -5.2，求代數(shù)式 a(-b-c)-3.2 a(c+ b)的值.-b(x-a) 2( x y)四、好好想一想1求滿足以下等式的x 的值2 5x -15x = 0 5x(x-2)-4(2-x) = 0參考答案103224、(1)4 x y (2) x(x + y)(3)2 a(2b-b+ 4)(4)( m n)(5 + mn)二、(1)D(2)D(3)A(4)C三、 x(x-y)-y(y-x) = (x-y)( x + y)322222(2) -12 x + 12xy-3 xy = -3x(4 x-4 xy+ y ) = -3 x(2x-y

4、)2 2(3) ( x + y) + mx+ my= (x+ y) + m(x + y) = (x+ y)( x+ y + m) a( x- a)( x+ y)2- b( x- a) 2( x+ y)=(x- a)( x+ y) a( x+ y)- b( x- a)=(x- a)( x+ y)( ax+ ay-bx+ ab)四、1.5x(x-3) = 0,那么 5x= 0, x-3 = 0, x = 0 或 x = 34(x-2)(5 x + 4) = 0,那么 x-2 = 0 或 5x+ 4= 0,.x= 2 或 x=-52.ta = -5 , a+ b+ c= -5.2 ,b+ c = -0.22 2a (- b-c)-3.2 a(c + b) = -a(b+ c)-3.2 a ( b+ c)=