发布时间 : 星期六 文章(word完整版)七年级数学下册第一章知识点总结更新完毕开始阅读670a3bc9bb1aa8114431b90d6c85ec3a86c28bf5
(3)(x2y)6·(x2y)3 (4)[(x?y)2n]4?(?x?y)2n?1 (n是正整数).
9.若(3x+2y-10)0无意义,且2x+y=5,求x、y的值.(6分)
整式的乘法及平方差公式与完全平方公式的运算
y?2y3)= 1.3x(x-2y)= ; ?4a(a-2b)= ; ?4x2(12x2y)(1(x2-2x?1)(-3x)= ; (-23xy?2x2xy)= (2x+5)(x-3)= ;(x-3y)( x-5y)= ;(2x-3y)( 3x-5y)=
3
2. 2x2y·(1-3xy+y)的计算结果是( ) 2A.2x2y4-6x3y2+x2y B.-x2y+2x2y4 C.2x2y4+x2y-6x3y2 D.-6x3y2+2x2y4 3. 计算(2x-1)(5x+2)的结果是( )
A.10x2-2 B.10x2-5x-2 C.10x2+4x-2 D.10x2-x-2 4.计算
5
①(a-3) ( a+3) ②2a(?2ab?ab2); ③y2(y?y2); ④3x2(-y-xy2+
1312x2);
⑤(?4xy)?(xy?3x2y); ⑥(?xy)(x2y?xy2?y); 1236
⑦(3x-2y)(2x-3y);
⑨(3x-2y)(3x+2y)
2325⑧(3x+2)(-x-2); ⑩( a+3)( a+3) 6