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[函数] 反三角

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guanmo1 Posted 2019-5-15 19:30 |Read mode
反三角.png

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isee Posted 2019-5-28 23:49
Last edited by isee 2019-5-29 00:10坑,试了几个,不是把看值与角弄反了,就是无整数解。。

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isee Posted 2019-5-30 13:21
Last edited by isee 2019-5-30 14:02再次粗略想了一下
$$75^\circ<\alpha\leqslant 90^\circ,4\sin\alpha =\sqrt{8+2\sqrt{10+2\sqrt{n}}},$$
相当于求非特殊角的三角函数精确值。

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isee Posted 2019-5-30 13:30
Last edited by isee 2019-5-30 14:01搜索了一下,在网上查到了一个
$$n=5,\alpha=81^\circ.$$
如何算的呢?

然后目测有
$$n=9,\alpha=90^\circ.$$

剩下的$n=6,7,8$就是未知了

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