化简:sin(3a-TT)/sina+cos(3a-TT)/cosa
问题描述:
化简:sin(3a-TT)/sina+cos(3a-TT)/cosa
答
-4cos2a
答
sin(3a-TT)/sina+cos(3a-TT)/cosa
=(sin(3a-TT)cosa+cos(3a-TT)sina)/(sinacosa)
=sin(3a-TT+a)/sinacosa
=2sin(4a-TT)/sin2a