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已知x,y均为正实数,且=+,则x+3y的最小值为 .
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高三下学期数学《》真题及答案
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已知abxy均为正实数且=1ab是常数则x+y的最小值为
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正实数xy满足xy+x+2y=6则xy的最大值为x+y的最小值为.
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