2021年苏科新版七年级数学下册《9.1单项式乘单项式》课后巩固提升训练题(附答案)
1.计算(﹣9a2b3)?8ab2=
.
2.(
)×ab=2ab2.
3.计算:(3x2)2?2x3=
.
4.用科学记数法表示计算结果:(3.5×103)×(﹣4×105)=
.
5.计算:(﹣2a)2?a3=
.
6.计算:(﹣3xy)2?(﹣x2z)=
.
7.长方形的长为3x2y,宽为2xy3,则它的面积为
8.计算:x4?2(﹣x2)?(﹣x)2?[﹣(﹣x2)3]4?2(﹣x)2的值为
.
9.计算:(﹣xy)3?(﹣x2)=
.
10.如果一个单项式与﹣3ab的积为﹣a2bc,则这个单项式为
.
11.计算:(﹣2a)2?3a=
.
12.已知单项式3x2y3与﹣5x2y2的积为mx4yn,那么m﹣n=
.
13.若两单项式ax﹣yb2,2abx+y是同类项,则这两个单项式的乘积是
.
14.x3y﹣2(x﹣1y)3=
.
15.如果a≠b,且(ap)3?bp+q=a9?b5成立,则q=
.
16.计算:2x?3x2=
.
17.若ab3=﹣2,则(﹣3ab)?2ab5=
.
18.计算:3x2?2x2y=
.
19.计算:xy2?(﹣6x)2=
.
20.计算:(1)x?x3+x2?x2.
(2)5x2y?(﹣2xy2)3.
(3)7x4?x5?(﹣x)7+5(x4)4.
21.计算:(1)(2x)3?(﹣5xy2);
(2)a3?a4?a+(a2)4+(﹣2a4)2.
23.计算3x3y3?(﹣x2y2)+(﹣x2y)3?9xy2.
24.计算:(x3y)?(﹣3xy2)3?(x)2.
25.(1)(﹣m4)3+(﹣m3)4﹣2m5?m7
(2)y2?3y﹣y?(﹣2y)2﹣(﹣y2)?y2
(3)(﹣3a2)3?a3+(﹣4a)2?a7﹣(5a3)3
(4)(p﹣q)2n÷(p﹣q)2n+1?(q﹣p)3(n是整数)
(5)0.510×210++3÷32
(6)﹣2﹣2﹣(﹣)﹣1++(﹣3)﹣1.
26.计算:
(1)(a3)2?(﹣2ab2)3
(2)a4?a4+(a2)4﹣(3a4)2.
(3)(﹣)﹣1+(﹣2)3×(π+3)0﹣()﹣3
(4)(3)12×()11×(﹣2)3.
参考答案
1.解:(﹣9a2b3)?8ab2=﹣9×8a2?a?b3?b2=﹣72a3b5.
故答案为:﹣72a3b5.
2.解:2b×ab=2ab2,
故答案为:2b.
3.解:(3x2)2?2x3=9x4?2x3=18x7.
故答案为:18x7.
4.解:(3.5×103)×(﹣4×105)=﹣14×108=﹣1.4×109.
故答案为:﹣1.4×109.
5.解:原式=4a2?a3=4a5,
故答案为:4a5.
6.解:原式=9x2y2?(﹣x2z)=﹣9x4y2z,
故答案为:﹣9x4y2z.
7.解:3x2y?2xy3=6x3y4,
8.解:x4?2(﹣x2)?(﹣x)2?[﹣(﹣x2)3]4?2(﹣x)2
=x4?(﹣2x2)?x2?x24?2x2=﹣4x4+2+2+24+2=﹣4x34,
故答案为:﹣4x34.
9.解:原式=﹣x3y3?(﹣x2)=x5y3.
故答案为:x5y3.
10.解:(﹣a2bc)÷(﹣3ab)=ac.
故答案是:ac.
11.解:原式=4a2?3a=12a3,
故答案为:12a3.
12.解:3x2y3×(﹣5x2y2)=﹣15x4y5,
∴mx4yn=﹣15x4y5,
∴m=﹣15,n=5
∴m﹣n=﹣15﹣5=﹣20
故答案为:﹣20
13.解:由题意可知:,
∴ab2?2ab2=2a2b4,
故答案为:2a2b4.
14.解:原式=x3y﹣2?(x﹣3y3)=y,
故答案为:y.
15.解:已知等式整理得:a3p?bp+q=a9?b5,
即,
解得:,
则q=2.
故答案为:2.
16.解:2x?3x2=6x1+2=6x3,
故答案为:6x3.
17.解:∵ab3=﹣2,
∴(﹣3ab)?2ab5=﹣6a2b6=﹣6(ab3)2=﹣6×(﹣2)2=﹣24,
故答案为:﹣24.
18.解:3x2?2x2y=6x4y.
故答案为:6x4y.
19.解:xy2?(﹣6x)2==12x3y2,
故答案为:12x3y2.
20.解:(1)原式=x4+x4=2x4;
(2)原式=5x2y?(﹣8x3y6)=﹣40x5y7;
(3)原式=7x4?x5?(﹣x7)+5x16=﹣7x16+5x16=﹣2x16.
21.解:(1)原式=8x3?(﹣5xy2)=﹣40x4y2;
(2)原式=a8+a8+4a8=6a8.
22.解:原式=3x3y3?(﹣x2y2)+(﹣x6y3)?9xy2=﹣2x5y5﹣x7y5.
23.解:原式=x3y?(﹣27x3y6)?x2=﹣x8y7.
24.解:(1)(﹣m4)3+(﹣m3)4﹣2m5?m7=﹣m12+m12﹣2m12=﹣2m12;
(2)y2?3y﹣y?(﹣2y)2﹣(﹣y2)?y2
=3y3﹣y?(4y2)+y4=3y3﹣4y3+y4=﹣y3+y4;
(3)(﹣3a2)3?a3+(﹣4a)2?a7﹣(5a3)3
=(﹣27a6)?a3+16a2?a7﹣125a9
=﹣27a9+16a9﹣125a9=﹣136a9;
(4)(p﹣q)2n÷(p﹣q)2n+1?(q﹣p)3(n是整数)
=﹣(p﹣q)2n﹣2n﹣1+3=﹣(p﹣q)2;
(5)0.510×210++3÷32=(0.5×2)10﹣+3÷9=110﹣+=1;
(6)﹣2﹣2﹣(﹣)﹣1++(﹣3)﹣1.=﹣+2+﹣=1.
25.解:(1)原式=a6?(﹣8a3b6)=﹣8a9b6;
(2)原式=a8+a8﹣9a8=﹣7a8;
(3)原式=﹣4+(﹣8)×1﹣8=﹣4﹣8﹣8=﹣20;
(4)原式=(×)11××(﹣8)=﹣25