求cos8°-sin7°×sin15°分之sin8°+sin7°cos15°的值

求cos8°-sin7°×sin15°分之sin8°+sin7°cos15°的值
求cos8°-sin7°×sin15°分之sin8°+sin7°cos15°的值

求cos8°-sin7°×sin15°分之sin8°+sin7°cos15°的值
(sin(15-7)+sin7cos15)/(cos(15-7)-sin7sin15)
=(sin(15)cos(7)-cos(15)sin(7)+)+sin7cos15))/cos(15)cos(7)+sin(15)sin(7)-sin7sin15)
=sin(15)cos(7)/cos(15)cos(7)
=tan(15)
＝tan(45-30)=(tan45-tan30)/(1+tan45*tan30)=0.26795.

用计算机算，这些都不是特殊角度，没办法化简结果的