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[函数] 2018四川初赛对数计算题目

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郝酒 Posted 2018-6-27 10:27 |Read mode
$$\frac{1-2\log_65\cdot\log_{10}3\cdot\log_{15}2}{\log_65\cdot\log_{10}3+\log_{10}3\cdot\log_{15}2+\log_{15}2\cdot\log_{6}5}$$

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kuing Posted 2018-6-27 10:39
记 `x=\ln2`, `y=\ln3`, `z=\ln5`,则 `\log_65=z/(x + y)`, `\log_{10}3=y/(z + x)`, `\log_{15}2=x/(y + z)`,代入即得。

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 Author| 郝酒 Posted 2018-6-27 14:20
算出来啦,感觉还是有点复杂呀!

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色k Posted 2018-6-27 18:35
就这丁点计算量都嫌复杂?

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