已知：x+y=3,xy=1,试求：_刷题宝

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已知：x+y=3,xy=1,试求：

上一题下一题 0.0难度选择题更新时间:2018-07-02 01:01:18

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已知二次函数y=﹣ $\frac{1}{2}$ x²﹣3x﹣ $\frac{5}{2}$ ，设自变量的值分别为x₁，x₂，x₃，且﹣3＜x₁＜x₂＜x₃，则对应的函数值y₁，y₂，y₃的大小关系是（）

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x

轴传播，实线为

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This summer, Mary, Tom, Alan are going to have an ideal vacation .
The followings are their plans for the coming vacation .

	Mary	Tom	Alan
Where ?	The Great Wall	Spain	Canada
When?	The first week in June	The last day of the May	June, Monday 18^th
Who ?	His parents	His best friends	His cousin
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How long?	About one month	Only two weeks	Until September
Transportation	By plane and by bus	By boat and by plane	By plane and by train

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