(sin7+cos15sin8)/(cos7+sin15sin8)

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(sin7+cos15sin8)/(cos7+sin15sin8)
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(sin7+cos15sin8)/(cos7+sin15sin8)
(sin7+cos15sin8)/(cos7+sin15sin8)

(sin7+cos15sin8)/(cos7+sin15sin8)
(sin7+cos15sin8)/(cos7-sin15sin8)
=sin(15-8)+cos15sin8)/(cos(15-8)-sin15sin8)
=(sin15cos8-cos15sin8+cos15sin8)/(cos15cos8+sin15sin8-sin15sin8)
=(sin15cos8)/(cos15cos8)
=sin15/cos15
=tan15
=2-√3
=(2cos10-sin20)/cos20
=[2cos(30-20)-sin20]/cos20
=(cos30cos20+2in30sin20-sin20)/cos20
=√3