内容正文:
3.(1)-2(2)b14(3)-x6(4)2x3(5)b
(2)7x-13x2y2-24y1(3)6a2-86
(6)a+2(7)(x+y)6(8)0(9)0(10)-(y-2)
(4)x3-3x2y+6.y2-8y3(5)6a3+7a2+8a
4.(1)3(2)6(3)10(4)40
(6)-
练习6幂的乘方与积的乘方
号-是r+6r+6r-4(1x2+6e
3.(1)5a-6(2)22m-23(3)x2+18x+72
1.(1)-a3b9(2)-a18
(3)(a-2)2m+2
(4)5.x-3x3-14x2+3x(5)2a6
(5)3a(6)(x+y)2
(6)4a-6a2+12
2.(1)256.x12(2)2y8(3)2x
练习10同底数幂的除法
3①2告
(2)10m+5
(3)2.7X105(4)2
1.(1)a(2)x6(3)-a4(4)x2y2(5)-2a
2
(6)-a3
4.(1)7(2)64(3)10000
2.(1)-1(2)a3
(3)-x4(4)a?(5)x2-x6
5.(1)2·102(2)10
(6)-a18(7)(b-a)(8)-2y
练习?单项式与单项式相乘
3.(1)200(2)2(3)39
1.(1)12ab(2)-6.x5y3(3)18m°n
412(2
(4)xy4
6)子y
5.(1)15
(3)400
2.(1)4x8y9(2)16x2y(3)17ab3
(4)-5a3b
练习11零指数幂与负整数指数幂
1
(5)3x4yx4
1.(1)-
27
8
(2)-
(3a (a 5
313a629a
2(3)-3ab
256
(4)
2.(1)0(2)1(3)-3(4)a8
o
1
3.(1)1
(3)10000
练习8单项式与多项式相乘
4.(1)3x2(2)n-m(3)0(4)-p
1.(1)6a3b-10ab2(2)x2y-6x3y2+2x2y
练习12同底数幂的混合运算
(3)-2x3y-8.x2y3(4)-6x3y2+4x2y-2xy
1.(1)-9
(2)-33)2(41(5)-9
1
(6)4
6)-42+2x-号x(6)-18a3+6a2+a
(7)1
2.0)-4a262+a6-4a62(2)-3y3+3xy
2.(1)a(2)-a0(3)-x(4)-x
(5)2y5-27y(6)b-a
(3)-4x2y2(4)-40a5b4+4ab5-2a3b
3.(1)-x4(2)am(3)-2x8(4)7(a-b)6
6)-a6-6a(oy-y+7y
4.3
5.解:3x+1X53x+1=152+4,.15x+1=152+4,.3x
)2-3x+4-4
+1=2x+4,∴.x=3.
3)-号y+信y
4
练习13
整式的乘法
(2)-6a3b+3a2b
1.(1)4x12(2)-
(3)-m3n5+2mn
y812ryg
w-a8-a6+子a6
(4)-9ab8
(5)2x2my6m(6)29ab-10a2-10b2
练习9多项式与多项式相乘
2.(1)xy(2)6a8(3)-4m3(4)-a2b2+ab+2
1.(1)2x2+5x-3(2)15x2+xy-2y
(5)-4a2+9a(6)6x3-x2+2x+2(7)-4a2b
(3)-6m2+m+2(4)6.x4+x2y-2y2
(5)x2+5x
125r8日
(9)6t3+t2+11t-5
1
(10)5x2+6a-1
3.5.x3+5x2-20x-20
·12·
练习14平方差公式与完全平方公式
(5)2x(x+y)(x-y)
1.(1)4x2-1(2)25a2b2-1(3)m2n2+2m+1
4.36
4-9m2(5)16x2-9y(6)4a2-962-66-1
5.x=-2,y=1
练习17因式分解(3)
2(D12)30号
(3)1(4)5
1.(1)2x(x+2)(x-2)(2)(a+b)2(a-b)2
(3)3mm(2m-51+10m)(4)-y(y-3x)2
1
3.(1)5a2-10ab+5b2(2)m2+4mm(3)2xy-2y
(5)3(x-2y)2(6)(a+2b+1)(a+2b-1)
(7)一3x(x+3)(x-3)(8)b(a-9)
(4)0(5)25-58m
4-青-7129y-+2x-
2解:原式=(y°(2x-y)=3”×号=9.
(3)9y2-6yz+x2-4x2-4x-1
及解:原武=ha+b产-号×2=18
练习15因式分解(1)》
4.解:原式=x·x2-x2-x十7=x(-x-1)-x2-
1.(1)2n(4m+1)(2)x"+(1+x2)(3)3x(x2-x
+7=-x2-x-x2-x+7=-2X(x2+x)+7=
+3)(4)7x(2mn+m+3n)(5)-4y(6.x2+3xy
-2×(-1)+7=9.
+7y2)(6)4x2yg2(x-222+3.x2yg)
5.解:原式=x(x一y十x)-y(x一y十x)+x(x一y十
(7)(a+b)(a-b-1)(8)ab(x-y)2(1-b)
2)=(x-y十z)(x-y十x)=-4×(-4)=16.
2.(1)(5+2xy)(5-2xy)
6解:1)原式-(1-)×(1+2)×(1-3)×(1
(2)(0.5g-11p)(0.5g+11p)
(3)(3ap+bq)(3ap-bq)
+3)×…×(1-)×(1+)=2×号×号×
④(3a-w)(3a+g)
,(2)原式=(2-1)+(4
(5)(2x+y-g)(y+x)(6)5(x+y)(y-x)
-32)+(6-52)+(10-92)+(142-132)-72=(2
(7)(2x-3)(2x-5)(8)(5a+2b+2c)(5a-2b-2c)
+1)×(2-1)+(4+3)×(4-3)+(6+5)×(6-5)
3.(1)(x-6y)2
(2(m-)'(3(x+号)
+(10+9)×(10-9)+(14+13)×(14-13)-49=3
+7+11+19+27-49=18.
(4)(5m+3m)2(5)(4a2+3b2)2
(6)(7x+2)2
练习18因式分解(4)》
(7)-(x-7y)2
(8)(9m-8n)2
(9(6a-1)月
1.(1)(x+1)(y-z)(2)(x-2y)(3+a)
(3)(x+2)(2x+1)(2x-1)(4)(x+y)2(x-y)
(10)(x+y+3)
(5)(a+b)(a-c)
4.(1)(x+2)2(x-2)2(2)(a+2)2(a-2)
2.(1)(x+7)(x+1)(2)(x-6)(x+1)
(3)(a2+9b2)(a-3b)(a+3b)(4)b(a-3)2
(3)(x-3)(x+2)(4)(x-7)(x+2)
(5)-3x(x+3)(x-3)(6)-3n(m-n)2
(5)(x+1)(x-1)(x+2)(x-2)(6)-3m(a-2)2
(7)(x-y十)2(8)(4m-n-3)(3n-2m-3)
3.解:(1)原式=x3-x2+x2-1=x2(x-1)+(x+
(9)21(x-2y)
1)(x-1)=(x-1)(x2+x+1).(2)原式=x4+
练习16因式分解(2)
4x2+4-4x2=(x2+2)2-4x2=(x2+2x+2)(x2
1.(1)(x2+9)(x-3)(x+3)(2)(x+2y)2(x-2y)2
-2x+2).(3)方法1:原式=x3一x-8x+8=(x3
(3)(x-1)2(x+1)2(4)8(2x+y)(x-2y)
-x)+(-8x+8)=x(x+1)(x-1)-8(x-1)=
(5)(3y+2x)(3y-2x)(9y2+4x2)
(x一1)(x2十x一8).方法2:原式=x3一x2+x2一
2.135998
9x+8=x2(x-1)+(x-8)(x-1)=(x-1)(x2+
(2)8008(3)1000000(4)4
x一8).方法3:原式=x3-9x-1+9=(x3-1)
3.(1)(x2-4y+1)(x-1)(x+1)
9x+9=(x-1)·(x2+x+1)-9(x-1)=(x
(2)2mm(m+n)(n-3m)
1)·(x2+x一8).方法4:原式=9x3一8x3-9x十
(3)(m-n)(m-2m)
8=(9x3-9x)+(-8x3+8)=9x(x+1)(x-1)
(4)3(a-b)(2a.x+2bx-3y)
8(x-1)(x2+x+1)=(x-1)(x2+x-8).
·13·七年级数学下QD
同行学案学练测计算高手
练习13整式的乘法
(难度等级:★★★)
V基础通关
(6)(3x2+2)(2x+1)-2x(2x+1)
1计算.
(1)(x3)4+3x9x3=
(2)(-3x2y3)3·(2xy)2=
(3)3x2y2·(-2xy2x)2=
(4)(-3a2b3)2·(-a3b2)=
()6a2(号ab-b3)-2a26(a-b)
(5)(x"y3m)2+(x2y)"=
(6)(2a-5b)(2b-5a)=
2.计算
号y(y}号
8(5x2(2s++y)
(2)a3·a·a4+(-2a4)2+(a2)4
(9)6t2-(2t-1)(-3t2+t-5)
(3)(-2mm2)2-4mn3(mn+1)
(10)(x十2)(2x2+1)-(2x-3)(x2+x-1)
(4)2(a2b2-ab+1)+3ab(1-ab)
V能力通关
3.已知f(x)=x2-x-2,g(x)-x2-6x+8,
p(x)=x2+3x+2,计算[f(x)-g(x)]·
(5)3a(2a2-4a+3)-2a2(3a-4)
b(x).
·13·
七年级数学下QD
同行学案学练测计算高手
练习14平方差公式与完全平方公式
(难度等级:★★)
V基础通关
(2)(2m+n)(2m-n)+(m+n)2-2(2m2-m)
1.计算.
(1)(2x+1)(-1+2x)=
(2)(5ab+1)(5ab-1)=
(3)(-mn-1)2=
(3(2x-3)(2x+2)-(2x-2)
(4(-3m+号)(经+3m)=
(5)(-4x-3y2)(3y2-4x)=
(6)(2a-3b-1)(2a+3b+1)=
2.计算.
(4)(x+y)(x-y)+(y-z)(y+x)+(x
x)(z+x)
(1)20232-2022×2024
220号x1
(5)(3m2+5)(-3m2+5)-m2(7m+8)(7m
3
8)-(8m)2
(3)10212-2040×1021+10202
V能力通关
4.计算
20
(4)1022-100×204+102
(2)(x+3y-x2)(-x+3y+x2)
3.计算.
(1)(3a-b)2-(2a+b)2+5b2
(3)(-2x+3y-之-1)(2x-之+3y+1)
·14