《乘法公式》练习题
一、填空题
1.(a+b)(a-b)=_____,公式的条件是_____,结论是_____.
2.(x-1)(x+1)=_____,(2a+b)(2a-b)=_____,( x-y)( x+y)=_____.
3.(x+4)(-x+4)=_____,(x+3y)(_____)=9y2-x2,(-m-n)(_____)=m2-n2
4.98×102=(_____)(_____)=(??? )2-(??? )2=_____.
5.-(2x2+3y)(3y-2x2)=_____.
6.(a-b)(a+b)(a2+b2)=_____.
7.(_____-4b)(_____+4b)=9a2-16b2,(_____-2x)(_____-2x)=4x2-25y2
8.(xy-z)(z+xy)=_____,( x-0.7y)( x+0.7y)=_____.
9.( x+y2)(_____)=y4- x2
10.观察下列各式:
(x-1)(x+1)=x2..