命题“存在x∈R，使得x2+2x+5=0”的否定是（  ）

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='19869' and id < 1724817 and id<>'1724817' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='19869' and id > 1724817 and id<>'1724817' order by id asc limit 5