对于实数a、b，定义一种运算“⊗”为：a⊗b=a2+ab﹣2，有下列命题：①1⊗3=2；②方程x⊗1=0的根为：x1=﹣2，x2﹣1；③不等式组的解集为：﹣1＜x＜4；④点（1，﹣2）在函数y=x⊗_刷题宝

题干

对于实数a、b，定义一种运算“⊗”为：a⊗b=a²+ab﹣2，有下列命题：

①1⊗3=2；②方程x⊗1=0的根为：x₁=﹣2，x₂﹣1；③不等式组的解集为：﹣1＜x＜4；④点（1，﹣2）在函数y=x⊗（﹣1）的图象上．

其中正确的是（　　）

A：①②③④

B：①③④

C：①②④

D：①②③

上一题下一题 0.0难度选择题更新时间:2016-01-22 05:47:36

答案(点此获取答案解析）

A

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