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提公因式法分解因式专项练习30 题(有答案)
1.27xy2﹣18x3y
2.(2a+b)(2a﹣b)+b(4a+2b)
3.a(x﹣y)﹣b(y﹣x)+c(x﹣y).
4.4x(a﹣b)﹣8y(b﹣a)
5.﹣4x3+8ax﹣4x.
6.(x﹣2)2+4(2﹣x)
7.2(x﹣y)(x+y)﹣(x+y)2
8.﹣2x2﹣12xy2+8xy3
9.(1)x(x﹣y)+y(y﹣x);
(2)
.
10.a3x2﹣a3y2.
11.2a(a﹣3)2﹣6a2(3﹣a)﹣8a(a﹣3).
12.﹣28m3n2+42m2n3﹣14m2n.
13.(a+2)(a﹣3)(a2﹣7)+(2+a)(3﹣a)(a+3)
14.(1)(x﹣1)(x﹣2)﹣2(2﹣x)2
(2)x2﹣y2﹣(x+y)2.
提公因式法分解因式---
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15.(a+b)2+(a+b)(a﹣3b)
16.ab(a﹣b)2﹣a2b(b﹣a)
17.x(x﹣y)﹣y(y﹣x)
18.x2(y﹣2)﹣x(2﹣y)
19.3a(x﹣y)﹣9b(y﹣x)
20.5(a﹣2)+10×(a﹣2).
21.15a2b2﹣5ab3.
22.3(x+y)(x﹣y)﹣(x﹣y)2.
23.2m(a﹣b)﹣3n(a﹣b).
24.5m(a﹣b)+20n(b﹣a)
25.x(x﹣y)﹣y(y﹣x)
26.(x+y)2﹣6(x+y)
27.2(1﹣m)2﹣3(m﹣1)
28.(3x+2y+1)2﹣(3x+2y﹣1)(3x+2y+1)
29.6a2b2﹣15a2b3+3a2b.
30.(1)6m2n﹣15n2m+30m2n2
(2)x(x﹣y)2﹣y(x﹣y)
提公因式法分解因式---
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参考答案:
1. 27xy2﹣18x3y=9xy(3y﹣2x2).
2.(2a+b)(2a﹣b)+b(4a+2b)=(2a+b)(2a﹣b)+2b(2a+b)=(2a+b)2.
3.a(x﹣y)﹣b(y﹣x)+c(x﹣y)=a(x﹣y)﹣b(y﹣x)+c(x﹣y)=(x﹣y)(a+b+c)
4.4x(a﹣b)﹣8y(b﹣a)=4x(a﹣b)+8y(a﹣b)=4(x+2y)(a﹣b).
5. ﹣4x3+8ax﹣4x=﹣4x(x2﹣2a+1).
6. 原式=(x﹣2)2+4(2﹣x)=(x﹣2)[(x﹣2)﹣4]=(x﹣2)(x﹣6).
7. 2(x﹣y)(x+y)﹣(x+y)2=(x+y)[2(x﹣y)﹣(x+y)]=(x+y)(x﹣3y).
8.﹣2x2﹣12xy2+8xy3=﹣2x(x+6y2﹣4y3).
9.(1)x(x﹣y)+y(y﹣x),=x(x﹣y)﹣y(x﹣y),=(x﹣y)(x﹣y),=(x﹣y)2;
(2)原式=(x+y)[(x+y)﹣1]+ ,=(x+y)2﹣(x+y)+ ,=(x+y+ )2
10.a3x2﹣a3y2=a3(x2﹣y2)=a3(x+y)(x﹣y).
11. 原式=2a(a﹣3)2+6a2(a﹣3)﹣8a(a﹣3)=2a(a﹣3)[(a﹣3)+3a﹣4]=2a(a﹣3)(4a﹣7).
12.原式=﹣(28m3n2﹣42m2n3+14m2n),=﹣14m2n(2mn﹣3n2+1).
13.(a+2)(a﹣3)(a2﹣7)+(2+a)(3﹣a)(a+3)=(a+2)(a﹣3)(a2﹣7)﹣(a+2)(a﹣3)(a+3),
=(a+2)(a﹣3)(a2﹣7﹣a﹣3)=(a+2)(a﹣3)(a2﹣a﹣10)
14.(1)(x﹣1)(x﹣2)﹣2(2﹣x)2=(x﹣1)(x﹣2)﹣2(x﹣2)2=(x﹣2)(x﹣1﹣2)=(x﹣2)(x﹣3);
(2)x2﹣y2﹣(x+y)2=(x+y)(x﹣y)﹣(x+y)2=(x+y)(x﹣y﹣x﹣y)=﹣2y(x+y)
15.(a+b)2+(a+b)(a﹣3b)=(a+b)(a+b+a﹣3b)=(a+b)(2a﹣2b)=2(a+b)(a﹣b).
16.ab(a﹣b)2﹣a2b(b﹣a)=ab(b﹣a)2﹣a2b(b﹣a)=ab(b﹣a)[(b﹣a)﹣a]=ab(b﹣a)(b﹣2a).
17. 原式=x(x﹣y)+y(x﹣y)=(x﹣y)(x+y)
18.原式=x2(y﹣2)+x(y﹣2),=x(y﹣2)(x+1).
19.原式=3a(x﹣y)+9b(x﹣y)=3(x﹣y)(a+3b).
20.5(a﹣2)+10×(a﹣2)=5(a﹣2)(1+2)=15(a﹣2)
21.原式=5ab2(3a﹣b).
22.原式=(x﹣y)[3(x+y)﹣(x﹣y)]=(x﹣y)(3x+3y﹣x+y)=(x﹣y)(2x+4y)=2(x﹣y)(x+2y)
23.2m(a﹣b)﹣3n(a﹣b),=(a﹣b)(2m﹣3n).
24. 原式=5m(a﹣b)﹣20n(a﹣b)=5(a﹣b)(m﹣4n).
25. x(x﹣y)﹣y(y﹣x)=x(x﹣y)+y(x﹣y)=(x﹣y)(x+y)
26.原式=(x+y)(x+y+6)
27. 2(1﹣m)2﹣3(m﹣1)=2(m﹣1)2﹣3(m﹣1)=(m﹣1)(2m﹣2﹣3)=(m﹣1)(2m﹣5).
28.原式=(3x+2y+1)[1﹣(﹣1)]=2(3x+2y+1)
29. 6a2b2﹣15a2b3+3a2b=﹣15a2b(b2﹣0.4b﹣0.2)=﹣15a2b(b﹣0.2+0.2
)(b﹣0.2﹣0.2
)
30.(1)6m2n﹣15n2m+30m2n2=3mn(2m﹣5n+10mn);
(2)x(x﹣y)2﹣y(x﹣y)=(x﹣y)(x2﹣xy﹣y).
提公因式法分解因式---