特殊三角函数值

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\sin{0^\circ}=0 \cos{0^\circ}=1 \tan{0^\circ}=0 \sin{3^\circ}=\dfrac{\sqrt{30}+\sqrt{10}-\sqrt{6}-\sqrt{2} }{16}-\dfrac{\sqrt{30}-\sqrt{10}+\sqrt{6}-\sqrt{2} }{32}\sqrt{10-2\sqrt{5} } \cos{3^\circ}=\dfrac{\sqrt{30}-\sqrt{10}-\sqrt{6}+\sqrt{2} }{16}+\dfrac{\sqrt{30}+\sqrt{10}+\sqrt{6}+\sqrt{2} }{32}\sqrt{10-2\sqrt{5} } \tan{3^\circ}=2+\sqrt{5}+\sqrt{15+6\sqrt{5} }-\dfrac{3\sqrt{3}+\sqrt{15}+\sqrt{5+2\sqrt{5} }+\sqrt{25+10\sqrt{5} }}{2} \sin{6^\circ}=\dfrac{\sqrt{30-6\sqrt{5} }-1-\sqrt{5} }{8} \cos{6^\circ}=\dfrac{\sqrt{15}+\sqrt{3}+\sqrt{10-2\sqrt{5} }}{8} \tan{6^\circ}=\dfrac{\sqrt{3}-\sqrt{15}+\sqrt{10-2\sqrt{5} }}{2} \sin{9^\circ}=\dfrac{1}{4}\sqrt{8-2\sqrt{10+2\sqrt{5}}} \sin{15^\circ}=\dfrac{1}{4}\sqrt{6}-\dfrac{1}{4}\sqrt{2} \cos{15^\circ}=\dfrac{1}{4}\sqrt{6}+\dfrac{1}{4}\sqrt{2} \tan{15^\circ}=2-\sqrt{3} \sin{18^\circ}=\dfrac{-1+\sqrt{5} }{4} \cos{18^\circ}=\dfrac{\sqrt{10+2\sqrt{5} }}{4} \tan{18^\circ}=\dfrac{\sqrt{25-10\sqrt{5} }}{5} \sin{22.5^\circ}=\dfrac{\sqrt{2-\sqrt{2} }}{2} \cos{22.5^\circ}=\dfrac{\sqrt{2+\sqrt{2} }}{2} \tan{22.5^\circ}=\sqrt{2}-1 \sin{30^\circ}=\dfrac{1}{2} \cos{30^\circ}=\dfrac{\sqrt{3} }{2} \tan{30^\circ}=\dfrac{\sqrt{3} }{3} \sin{36^\circ}=\dfrac{\sqrt{10-2\sqrt{5} }}{4} \cos{36^\circ}=\dfrac{1+\sqrt{5} }{4} \tan{36^\circ}=\sqrt{5-2\sqrt{5} } \sin{37.5^\circ}=\dfrac{\sqrt{8-2\sqrt{6}+2\sqrt{2} }}{4} \cos{37.5^\circ}=\dfrac{\sqrt{8+2\sqrt{6}-2\sqrt{2} }}{4} \tan{37.5^\circ}=\sqrt{15-6\sqrt{6}-8\sqrt{3}+10\sqrt{2} } \sin{45^\circ}=\dfrac{\sqrt{2} }{2} \cos{45^\circ}=\dfrac{\sqrt{2} }{2} \tan{45^\circ}=1 \sin{54^\circ}=\dfrac{1+\sqrt{5} }{4} \cos{54^\circ}=\dfrac{\sqrt{10-2\sqrt{5} }}{4} \tan{54^\circ}=\sqrt{5-2\sqrt{5} }+\dfrac{2\sqrt{25-10\sqrt{5} }}{5} \sin{60^\circ}=\dfrac{\sqrt{3} }{2} \cos{60^\circ}=\dfrac{1}{2} \tan{60^\circ}=\sqrt{3} \sin{72^\circ}=\dfrac{\sqrt{10+2\sqrt{5} }}{4} \cos{72^\circ}=\dfrac{\sqrt{5}-1}{4} \tan{72^\circ}=\sqrt{5+2\sqrt{5} } \sin{75^\circ}=\dfrac{\sqrt{6}+\sqrt{2} }{4} \cos{75^\circ}=\dfrac{\sqrt{6}-\sqrt{2} }{4} \tan{75^\circ}=2+\sqrt{3} \sin{84^\circ}=\dfrac{1}{8}\sqrt{15}+\dfrac{1}{8}\sqrt{3}+\dfrac{1}{8}\sqrt{10-2\sqrt{5}} \cos{84^\circ}=\dfrac{\sqrt{30-6\sqrt{5} }-1-\sqrt{5} }{8} \sin{87^\circ}=\dfrac{\sqrt{30}-\sqrt{10}-\sqrt{6}+\sqrt{2} }{16}+\dfrac{\sqrt{30}+\sqrt{10}+\sqrt{6}+\sqrt{2} }{32}\sqrt{10-2\sqrt{5} } \cos{87^\circ}=\dfrac{\sqrt{30}+\sqrt{10}-\sqrt{6}-\sqrt{2} }{16}-\dfrac{\sqrt{30}-\sqrt{10}+\sqrt{6}-\sqrt{2} }{32}\sqrt{10-2\sqrt{5} } \sin{90^\circ}=1 \cos{90^\circ}=0