平方差公式
◆基础训练
1.(a2b2)(a2-b2)(____)2-(____)2______.
2.(-2x2-3y2)(2x2-3y2)(____)2-(____)2_____.
3.20×19(20____)(20-____)_____-__________.
4.93×107(____-_____)(________)____-_____.
5.20062-2005×2007的计算结果为()
A.1
B.-1
C.2
D.-2
6.在下列各式中,运算结果是b2-16a2的是()
A.(-4ab)(-4a-b)B.(-4ab)(4a-b)
C.(b2a)(b-8a)
D.(-4a-b)(4a-b)
7.运用平方差公式计算.(1)102×98
(2)23×3144
(3)-27×33
(4)1007×993
(5)121×11233
(6)-194×20155
(7)(3a2b)(3a-2b)-b(a-b)(8)(a-1)(a-2)(a1)(a2)
(9)(ab)(a-b)(a2b)(a-2b)(10)(x2y)(x-2y)-(2x5y)(2x-5y)
1
f(11)(2m-5)(52m)(-4m-3)(4m-3)
(12)(ab)(a-b)-(a-3b)(a3b)(-2a3b)(-2a-3b)
◆综合应用8.(3ab)(____)b2-9a2;(ab-m)(____)b2-(a-m)2.9.先化简,再求值(3a1)(3a-1)-(2a-3)(3a2),其中a-1.
3
10.运用平方差公式计算
(1)
2005
;
20052200042006
(2)99×101×10001.
11.解方程(1)2(x3)(x-3)x2(x-1)(x1)2x
(2)(2x-1)(2x1)3(x2)(x-2)(7x-1)(x1)
12.计算:(4x-3y-2ab)2-(4x3y2a-b)2.
2
f◆拓展提升13.若ab4,a2-b212,求a,b的值.
完全平方公式
◆基础训练
1.完全平方公式:(ab)2______,(a-b)2______.即两数的_____的平方
等于它们的_____,加上(或减去)________.
2.计算
(1)(2a1)2(_____)22_________(____)2________;
(2)(2x-3y)2(_____)2-2_________(_____)2_______.
3.(____)2a212ab36b2;(______)24a2-12ab9b2.
4.(3xA)29x2-12xB,则A_____,B______.
5.m2-8m_____(m-_____)2.
6.下列计算正确的是()
A.(a-b)2a2-b2
B.(a2b)2a22ab4b2
C.(a2-1)2a4-2a21
D.(-ab)2a22abb2
7.运算结果为1-2ab2a2b4的是()
A.(-1ab2)2B.(1ab2)2C.(-1a2b2)2D.(-1-ab2)2
8.计算(x2y)2-(3x-2y)2的结果为()
A.-8x216xyB.-4x216xyC.-4x2-16xyD.8x2-16xy
9.计算(a1)(-a-1)的结果是()
A.-a2-2a-1B.-a2-1
C.a2-1
D.-a22a-1
10.运用完全平方公式计算
(1)(a3)2
(2)(5x-2)2
(3)(-13a)2
3
f(4)(1a1b)235
(5)(-a-b)2
(6)(-a1)22
(7)(xy4)2
(8)(a1)2-a2
(9)(-2m2-1
2)22
(10)1012
(11)1982
(12r