(-5a2+4b2)( )=25a4-16b4,括号内应填( )A.5a2+4b2B.5a2-4b2C.-5a2-4b2D.-5a2+4b2
题型:单选题难度:简单来源:不详
(-5a2+4b2)( )=25a4-16b4,括号内应填( )A.5a2+4b2 | B.5a2-4b2 | C.-5a2-4b2 | D.-5a2+4b2 |
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答案
∵(-5a2+4b2)(-5a2-4b2)=25a4-16b4, ∴应填:-5a2-4b2. 故选C. |
举一反三
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