原式分子=3sin^2(x/2) - 2sinx + cos^2(x/2)
=3sin^2(x/2) + 3cos^2(x/2) -2cos^2(x/2) - 2sinx
=2 + 1 - 2cos^2(x/2) - 2sinx
=2 - cosx - 2sinx
原式分母= tanx
故原式得到你答案所示.
原式分子=3sin^2(x/2) - 2sinx + cos^2(x/2)
=3sin^2(x/2) + 3cos^2(x/2) -2cos^2(x/2) - 2sinx
=2 + 1 - 2cos^2(x/2) - 2sinx
=2 - cosx - 2sinx
原式分母= tanx
故原式得到你答案所示.