内容正文:
计算题专项突破之整式乘法2025-2026学年苏科版
七年级下册(八大板块)
板块一:单项式乘单项式
1.计算:(-xy2)·(2xy)3.
2.计算:(-青x2y)3.(-2xy22)2.
3.计算:-2x2yz(-言xy2z(9xyz习
4.计算:
(1)3x2y-2x2,(2)(5ab2)(-2a2bc);
(3)-5a2b(-3a);(4)-2x"y·-x3y")-5xy)
板块二:单项式乘多项式
1.计算:-3a·(a2-ab+2b2).
2.计算:(-2xy习·(保y2-x2-xy)
3.计算:9x(-2x2-xy+y2)(-xy).
4.计算:
a42x2+3x-,@(后ab-26j(bj
5.计算:
(①5m-n+2:2-2x3x2-4-2:3)3x3x2+g-2:④2a-2ab+写b
板块三:多项式乘多项式
1.计算:(x+5y)(2x-y).
2.计算:(-7x2-8y2)·(-x2+3y2):
3.计算:(2a-5b)·(3a2-2ab+b).
4.计算:
(1)(x-1x2+x+1(2)(x+3)(x-2-xx-
板块四:平方差公式
1.运用平方差公式计算:
(1)(x+30x-3x2+9):
@xr++
2.计算:
(1)(-3x2-5y3x2-5y);(2)(9x2+10(1-3x(-3x-1).
3.利用乘法公式计算下列各题:
2*川2x-列:②后x+5j后x-5月
(3)(x+3(x-3(x2+9;
④(++》
板块五:完全平方公式
1.计算
2x-+-3
2.计算:
a-a+,e2j:8得a-j:(m+
3.计算:
(1)(1+42;(2)(-5+3y)2;(3)(x2-6y;
④(-2x62a+-aa-:6合+2yj-+行-2y
板块六:用乘法公式进行简便运算
1.简便方法计算:30002-2998×3002.
2.运用乘法公式计算:
(1)30号×29;(2)1.352+2×1.35×2.65+2.652.
3.运用完全平方公式计算:
(1)632;(2)982:(3)700.12;(4)499.92.
4.用简便方法计算:
(1)101×99(2)32×22+14×23+10×24
5.用简便方法计算:
(1)101×99;(2)20222-2023×2021.(
-g)
板块七:整式乘法综合运算
1.计算
(1)4xy-3y+2y6xy+2(2)(a-1)(a-3)-a(a-4)
2.计算:
(1)(-2a·ab2(2)(x+y(x-3y川+2xy-x
3.(1)计算:x·2x+xx-2;(2)(m+1(m-5)-mm-6)
4.计算:
(1)(a-1)(a2+a+1);(2)(2x+5)(2x-5)-(x+1)(x-4);
(3)(3x-2)(2x+3)(x-2).
5.计算:
(1)a2.a6-(-2a4)2,2)(1+a)(1-a)+(a+3)2
板块八:整式乘法化简求值
1.先化简,再求值(m+2mm-2ma+4加),其中m=3,=
2.先化简、再求值:x2.(16xy-4y2)-4xy+4x2y2,其中x=2,y=-1.
3.化简求值:(x-y)(y-x)-[-y2+2x(x-y)],其中x=,y=-2.
4.(1)已知a+吉=3,求a2+专的值;
(2)已知(a-b)2=9,ab=18,求a2+b2的值.
【答案】
计算题专项突破之整式乘法2025-2026学年苏科版
七年级下册(八大板块)
板块一:单项式乘单项式
1.计算:(-xy2)·(2xy)3.
【答案】解:原式=(-xy2)·8xy
=-8x4y5.
2.计算:(-青xy)3.(-2xy22)2.
【答案】解:(-青xy)3。(-2x22)2
=-xy34x2y42
=-号2
3.计算:-2x2yz(-言xy2z(9xyz2),
【答案】解:-2x2yz·(-言xy2z(9xyz习
=2×言×9x2+1+1y1+2+1z1+1+2
=3x4y4z4.
4.计算:
(1)3x2y2x2,(2)(5ab2)(-2a2bc);
(3)(-5a2b)(-3a);(④(-2xy)-xy)-5xy).
【答案】(1)6xy(2)-10abc(3)15a3b(4-10xm+4y2m*3
【详解】(1)解:3x2y2x2=6x4y:
(2)解:(5ab2)-2a2bc】
=-2x5(a.a2)-(b2.b).c
=-10a3b3c;
(3)解:(-5ab)(-3a)
=5×3a2.ab
=15a3b;
(4)解:(-2xy)小(-xy)-5xw)
=-2×5xxx小yyy)
=-10xm+4y2m*3
板块二:单项式乘多项式
1.计算:-3a·(a2-ab+2b2).
【答案】解:原式=-3a3+3a2b-6ab2.
2.计算:(-2xy网2.(y2-x2-xy,
【答案】解:原式=4xy4(寺2-专2-xy)
=x2y5-2x4y4-6x3y5.
3.计算:9x(-2x2-xy+y2)(-xy).
【答案】解:9x(-2x2-xy+y2)(-xy)
=-9x2y(-2x2-xy+y2)
=18x4y+9xy2-9x2y3.
4.计算:
4 2-2)--ob).
【答案】(①8x2+12r2-42)-ab+a6
【详解】(1)解:4x2x2+3x-1
=4x2x2+4x3x+4x-1
=8x3+12x2-4x
(2)解:
(s-2aj
2
+ai
5.计算:
05mm-n+2:2-2x3r-4x-2刘:33x(3r+w-2:④2a-2ab+5b
【答案】(05m2-5mn+10m②)-6x3+8x2+4x(3)9x+3xy-3xy2(4④-4a2b+2a2b2
【详解】(1)解:5m(m-n+2
=5m·m-5m·n+5mx2
=5m2-5mn+10m;
(2)解:(-2x)(3x2-4x-2
=-2x)×3x2-(-2x)×4x-(-2x×2
=-6x3+8x2+4x;
(3)解:3x2(3x2+y-y2)
=3x2×3x2+xy×3x2-y2x3x2
=9x4+3x3y-3x2y2,
(4)解:2a-2ab+ab2
3
=2a(-2ab)+2a×5ab2
=-4ab+2ab.
3
板块三:多项式乘多项式
1.计算:(x+5y)(2x-y).
【答案】解:(x+5y)(2x-y)
=2x2-xy+10xy-5y2
=2x2+9xy-5y2.
2.计算:(-7x2-8y2)·(-x2+3y2):
【答案】解:原式=7x4-21x2y2+8x2y2-24y4
=7x4-13x2y2-24y;
3.计算:(2a-5b)·(3a2-2ab+b2).
【答案】解:(2a-5b)·(3a2-2ab+b2)
=2a·(3a2-2ab+b2)-5b·(3a2-2ab+b2)
=6a3-4a2b+2ab2-(15a2b-10ab2+5b3)
=6a3-4a2b+2ab2-15a2b+10ab2-5b3
=6a3-19a2b+12a-5b3.
4.计算:
(1)(x-1(x2+x+1(2)(x+3)(x-2)-xx-1
【答案】(1)x3-1(2)2x-6
【详解】(1)解:(x-1)(x2+x+1
=x3+x2+x-x2-x-1,
=x3-1:
(2)解:(x+3)(x-2-xx-1,
=x2-2x+3x-6-x2-x,
=x2+x-6-x2+x,
=x2-x2)+(x+x)-6,
=2x-6
板块四:平方差公式
1.运用平方差公式计算:
(1)(x+3)(x-3)(x2+9);
@(+*
【答案1①x-812)6
【详解】(1)解:(x+3)(x-3)(x2+9)
=(x2-9)(x2+9)
=x4-81:
2)解:〔++
(+