1+cosx+cosx/2 помогите

Question

1+cosx+cosx/2 помогите

Answer 1

1+cos x + cos x/2 = 1+ cos 2.x/2 + cos x/2=
=1+ cos ˇ2 x/2 - sinˇ2 x/2 + cos x/2 = 1-sinˇ2 x/2 + cosˇ2 x/2 + cos x/2 =
=cosˇ2 x/2 + cosˇ2 x/2 + cos x/2 = 2.cosˇ2 x/2 + cos x/2 =
=cos x/2 .(2.cos x/2 + 1)

Comments

ответ4 соsx/4cos(x/4+пи/6)сos(x/4-пи/6)