若命题p：任意x∈R,2x2－1＞0，则该命题的否定是( )

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若命题p：任意x∈R,2x²－1＞0，则该命题的否定是( )

A：任意 $x \in R$ ,2x²-1<0

B：任意 $x \in R$ , $2 x^{2} - 1 \leq 0$

C：存在 $x \in R$ , $2 x^{2} - 1 \leq 0$

D：存在 $x \in R$ ,2x2-1>0

上一题下一题 0.0难度选择题更新时间:2013-11-26 05:46:48

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C

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根据材料内容，选择正确答案。

There are 50 students in Class 8. Now they are doing a survey about how they spend their pocket money. Some spend it on books, and others spend it on visiting. What about you? Please read the form and answer the questions.

10%	55%	12%	10%	13%
Buy some CDs and computer games.	Buy some snacks and drinks.	Buy some books in the bookshop.	Save it up and spend it traveling on holiday.	Buy some gifts for friends.

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