2021-2022学年北师大版七年级数学下册《1-7整式的除法》同步练习(附答案)
1.已知长方形面积为6y4﹣3x2y3+x2y2,它的一边长为3y2,则这个长方形另外一边长为 .
2.计算:(14a2﹣7a)÷7a= .
3.长方形的面积为4a2﹣6ab+2a,长为2a,则它的周长为 .
4.计算:(18x3﹣48x2+6x)÷6x= .
5.(8a3b﹣4a2b2)÷2ab= .
6.(16x3﹣8x2+4x)÷(﹣2x)= .
7.对于任意实数,若规定=ad﹣bc,则当x2﹣2x﹣5=0时,= .
8.计算:(2m2﹣m)2÷(﹣m2).
9.计算:(x+2y)2+(x+2y)(x﹣2y)+(x3﹣3x2y)÷x.
10.计算:(12a4﹣4a3﹣8a2)÷(2a)2.
11.先化简,再求值:[(x﹣y)2+(x﹣y)(x+y)]÷2x,其中x=﹣3,y=15.
12.计算:(x+y)(x﹣y)﹣(4x3y﹣4xy3)÷2xy.
13.先化简,再求值:[(x﹣3y)2﹣x(2x﹣4y)+x2]÷(﹣2y),其中x=1,y=2.
14.计算:
(1)(4a2b+6a2b2﹣ab2)÷2ab; (2)(2x+1)(3x2﹣2x+2).
15.先化简,再求值:[(x+y)(x﹣y)﹣(x﹣y)2+2y(x﹣y)]÷4y,其中x=-5,y=1.
16.已知长方形的面积为4a2﹣6ab+2a,它的一边长为2a.
(1)求这个长方形的另一边长;
(2)求这个长方形的周长.
17.化简:
(1)2a(2a+5)﹣(2a+1)2;
(2)[(2x+y)(2x﹣y)﹣3(2x2﹣xy)+y2]÷(﹣x).
18.先化简,再求值:[(x﹣2y)2+(x﹣2y)(x+2y)﹣2x(2x﹣y)]÷2x,其中x=3,y=﹣3.
19.先化简,再求值:(x+y)(x﹣y)﹣(4x3y﹣8xy3)÷2xy,其中x=1,y=﹣2.
20.计算:(9a5﹣15a3+6a)÷3a.
21.先化简,再求值:(2m+3)(2m﹣3)﹣(m+2)2+4(m+3),其中m=﹣.
22.先化简,再求值:(a+3)2﹣(a+1)(a﹣1)﹣2(2a+4),其中a=.
23.先化简,再求值.
(x+y)(x﹣y)﹣(4x3y﹣8xy3)÷2xy,其中x=﹣1,y=﹣.
24.先化简,再求值:[(x+2y)2﹣(x+y)(3x﹣y)﹣5y2]÷2x,其中x=﹣2,y=.
25.任意给定一个非零数a,按下列程序计算.
(1)请用含a的代数式表示计算程序,并给予化简.
(2)当输入的数a=1时,求输出结果.
26.化简:
(1)(﹣x2y)2 (﹣4xy2)÷(x3y);
(2)(2y﹣x)(x+2y)﹣(x+2y)2.
27.先化简,再求值:[(x﹣2y)2﹣2(x+y)(x﹣y)﹣6y2]÷(2x),其中x=2,y=.
28.先化简,再求值:(a﹣1)2+(2a3﹣a2)÷a2,其中a=﹣3.
参考答案
1.解:长方形另一边长为:
(6y4﹣3x2y3+x2y2)÷3y2
=2y2﹣x2y+x2,
故答案为:2y2﹣x2y+x2.
2.解:(14a2﹣7a)÷7a
=14a2÷(7a)﹣7a÷(7a)
=2a﹣1.
故答案为:2a﹣1.
3.解:∵长方形的面积为4a2﹣6ab+2a,它的长为2a,
∴它的宽为:(4a2﹣6ab+2a)÷2a
=4a2÷2a﹣6ab÷2a+2a÷2a
=2a﹣3b+1,
∴它的周长为:2(2a﹣3b+1+2a)
=8a﹣6b+2.
故答案为:8a﹣6b+2.
4.解:(18x3﹣48x2+6x)÷6x
=18x3÷6x﹣48x2÷6x+6x÷6x
=3x2﹣8x+1.
故答案为:3x2﹣8x+1.
5.解:(8a3b﹣4a2b2)÷2ab
=8a3b÷2ab﹣4a2b2÷2ab
=4a2﹣2ab.
故答案为:4a2﹣2ab.
6.解:(16x3﹣8x2+4x)÷(﹣2x),
=16x3÷(﹣2x)+(﹣8x2)÷(﹣2x)+4x÷(﹣2x),
=﹣8x2+4x﹣2.
7.解:∵x2﹣2x﹣5=0,
∴x2﹣2x=5,
则原式=(x+1)(x﹣1)﹣x(4﹣x)
=x2﹣1﹣4x+x2
=2x2﹣4x﹣1
=2(x2﹣2x)﹣1
=10﹣1
=9.
故答案为:9.
8.解:原式=(4m4﹣4m3+m2)÷(﹣m2)
=﹣4m2+4m﹣1.
9.解:原式=x2+4xy+4y2+x2﹣4y2+x2﹣3xy
=3x2+xy.
10.解:原式=(12a4﹣4a3﹣8a2)÷4a2
=3a2﹣a﹣2.
11.解:原式=(x2﹣2xy+y2+x2﹣y2)÷2x
=(2x2﹣2xy)÷2x
=x﹣y,
当x=﹣3,y=15时,
原式=3﹣15=﹣18.
12.解:(x+y)(x﹣y)﹣(4x3y﹣4xy3)÷2xy
=x2﹣y2﹣(2x2﹣2y2)
=x2﹣y2﹣2x2+2y2
=﹣x2+y2.
13.解:原式=(x2﹣6xy+9y2﹣2x2+4xy+x2)÷(﹣2y)
=(﹣2xy+9y2)÷(﹣2y)
=﹣2xy÷(﹣2y)+9y2÷(﹣2y)
=x﹣y,
当x=1,y=2时,
原式=1﹣×2
=1﹣9
=﹣8.
14.解:(1)(4a2b+6a2b2﹣ab2)÷2ab
=4a2b÷2ab+6a2b2÷2ab﹣ab2÷2ab
=2a+3ab﹣.
(2)(2x+1)(3x2﹣2x+2)
=2x 3x2+2x (﹣2x)+2x 2+1 3x2+1 (﹣2x)+1×2
=6x3﹣4x2+4x+3x2﹣2x+2
=6x3﹣x2+2x+2.
15.解:原式=(x2﹣y2﹣x2+2xy﹣y2+2xy﹣2y2)÷4y
=(﹣4y2+4xy)÷4y
=x﹣y,
当x= -5,y=1时,原式=-5-1=-6.
16.解:(1)∵长方形的面积为4a2﹣6ab+2a,它的一边长为2a,
∴(4a2﹣6ab+2a)÷(2a)=2a﹣3b+1,
∴长方形的另一边长为2a﹣3b+1;
(2)L=2×(2a﹣3b+1+2a)=8a﹣6b+2,
∴这个长方形的周长为8a﹣6b+2.
17.解:(1)2a(2a+5)﹣(2a+1)2
=4a2+10a﹣4a2﹣4a﹣1
=6a﹣1;
(2)[(2x+y)(2x﹣y)﹣3(2x2﹣xy)+y2]÷(﹣x)
=(4x2﹣y2﹣6x2+3xy+y2)÷(﹣x)
=(﹣2x2+3xy)×(﹣)
=﹣2x2×(﹣)+3xy×(﹣)
=4x﹣6y.
18.解:原式=(x2﹣4xy+4y2+x2﹣4y2﹣4x2+2xy)÷2x
=(﹣2x2﹣2xy)÷2x
=﹣x﹣y,
当x=3,y=﹣3时,原式=﹣3﹣(﹣3)=0.
19.解:原式=x2﹣y2﹣(2x2﹣4y2)
=x2﹣y2﹣2x2+4y2
=﹣x2+3y2,
当x=1,y=﹣2时,
原式=﹣12+3×(﹣2)2
=﹣1+12
=11.
20.解:原式=9a5÷3a﹣15a3÷3a+6a÷3a
=3a4﹣5a2+2.
21.解:(2m+3)(2m﹣3)﹣(m+2)2+4(m+3)
=4m2﹣9﹣m2﹣4m﹣4+4m+12
=3m2﹣1,
当m=﹣时,原式=3×(﹣)2﹣1=﹣.
22.解:原式=a2+6a+9﹣(a2﹣1)﹣4a﹣8
=2a+2,
∵a=,
∴原式=1+2=3.
23.解:(x+y)(x﹣y)﹣(4x3y﹣8xy3)÷2xy
=x2﹣y2﹣2x2+4y2
=﹣x2+3y2,
当x=﹣1,y=﹣时,原式=﹣(﹣1)2+3×()2=﹣1+3×=﹣1+=﹣.
24.解:原式=(x2+4xy+4y2﹣3x2+xy﹣3xy+y2﹣5y2)÷2x=(﹣2x2+2xy)÷2x=﹣x+y,
当x=﹣2,y=时,原式=2.
25.解:(1)由题意可得,
计算程序为:(2a2﹣4a)÷a﹣3a+5,
(2a2﹣4a)÷a﹣3a+5
=2a﹣4﹣3a+5
=﹣a+1,
即运算程序为(2a2﹣4a)÷a﹣3a+5,化简后的结果为﹣a+1;
(2)当a=1时,输出结果为﹣1+1=0,
即当输入的数a=1时,输出结果是0.
26.解:(1)原式=(x4y2) (﹣4xy2)÷(x3y)
=﹣4x2y3;
(2)原式=4y2﹣x2﹣x2﹣4xy﹣4y2
=﹣4xy﹣2x2.
27.解:原式=(x2﹣4xy+4y2﹣2x2+2y2﹣6y2)÷(2x)
=(﹣x2﹣4xy)÷(2x)
=x﹣2y,
当x=2,y=时,
原式=﹣×2﹣2×(﹣)
=﹣1+1
=0.
28.解:原式=a2﹣2a+1+2a﹣1
=a2,
当a=﹣3时,原式=(﹣3)2=9.