有下列四个命题：①“若x+y=0 , 则x,y互为相反数”的逆命题；②“全等三角形的面积相等”的否命题；③“若q≤1,则x2+2x+q=0有实根”的逆否命题；④“存在α,β∈R，使sin(α+β)=s_刷题宝

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有下列四个命题：
①“若x+y=0 , 则x,y互为相反数”的逆命题；
②“全等三角形的面积相等”的否命题；
③“若q≤1 ,则x²+2x+q=0有实根”的逆否命题；
④“存在α,β∈R，使sin(α+β)=sinα+sinβ成立”的否定．
其中真命题为（）

A：①②

B：②③

C：①③

D：③④

上一题下一题 0.0难度选择题更新时间:2018-07-25 05:08:20

答案(点此获取答案解析）

C

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