sin21cos9-cos84^(@)cos6

sin21^(@)cos9^(@)-cos84^(@) cos6^(@)=

Prove that sin21^(@)cos9^(@)-cos84^(@)cos6^(@)=1/4 .

(The24^(@)cos6^(@)-sin6^(@)sin66^(@))/(sin21^(@)cos39^(@)-cos51^(@)sin69^(@)) is

The value of (sin24^(@)cos6^(@)-sin6^(@)sin66^(@))/(sin21^(@)cos39^(@)-cos51^(@)sin69^(@)) is

A=sin78^(@)-sin18^(@)+cos132^(@) B=cos12^(@)+cos84^(@)+cos132^(@)+cos156^(@) and C=(sin 75^(@)+sin 15^(@))/(cos 75^(@)+cos 15^(@)) then arrange in the ascending order

A.78^(@)-sin18^(@)+cos132^(@),B=cos12^(@)+cos84^(@)+cos132^(@)+cos156^(@) and C=(sin75^(@)+sin15^(@))/(cos75^(@)+cos15^(@)) then arrang in the ascending order

Prove that, sin51^(@)+cos81^(@)=cos21^(@)

Prove that sin51^(@)+cos81^(@)=cos21^(@) .

cos12^(@)+cos60^(@)+cos84^(@)=cos24^(@)+cos48

Find the value of cos12^(@)+cos84^(@)+cos156^(@)+cos132^(@) .