题目内容
下列式子正确的是( )
A.(a+5)(a-5)=a2-5 | B.(a-b)2 = a2-b2 |
C.(x+2)(x-3)=x2-5x-6 | D.(3m-2n)(-2n-3m)=4n2-9m2 |
D
试题分析:根据整式的混合运算法则依次分析各选项即可作出判断.
A、



D、

点评:计算题是中考必考题,一般难度不大,学生要特别慎重,尽量不在计算上失分.

练习册系列答案
相关题目