题目 编号:84

已知a,b为非零实数,且a<b,则下列命题成立的是(    )",

A.http://static.vko.cn/content/tk/import/20150823152104/image001.png<http://static.vko.cn/content/tk/import/20150823152104/image002.png

B.http://static.vko.cn/content/tk/import/20150823152104/image003.png<http://static.vko.cn/content/tk/import/20150823152104/image004.png

C.http://static.vko.cn/content/tk/import/20150823152104/image005.png<http://static.vko.cn/content/tk/import/20150823152104/image006.png

D.http://static.vko.cn/content/tk/import/20150823152104/image007.png<http://static.vko.cn/content/tk/import/20150823152104/image008.png

答案及解析

答案

C

解析

若a<b<0,则a2>b2,故A错;若ab>0则a2b<ab2,故B错; 若ab<0,a<b则a2b> ab2,则http://static.vko.cn/content/tk/import/20150823152104/image005.png<http://static.vko.cn/content/tk/import/20150823152104/image006.png,故C正确.若0<a<b,则http://static.vko.cn/content/tk/import/20150823152104/image007.png>http://static.vko.cn/content/tk/import/20150823152104/image008.png,故D错.故选C.

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