sin6°*cos24°*sin78°*cos48°
=sin6°*cos24°*cos12°*cos48°
=16cos6°sin6°*cos24°*cos12°*cos48°/(16cos6°)
=8sin12°*cos12°*cos24°*cos48°/(16cos6°)
=4sin24°*cos24°*cos48°/(16cos6°)
=2sin48°*cos48°/(16cos6°)
=sin96°/(16cos6°)
=cos6°/(16cos6°)
=1/16
sin6°*cos24°*sin78°*cos48°
=sin6°*cos24°*cos12°*cos48°
=16cos6°sin6°*cos24°*cos12°*cos48°/(16cos6°)
=8sin12°*cos12°*cos24°*cos48°/(16cos6°)
=4sin24°*cos24°*cos48°/(16cos6°)
=2sin48°*cos48°/(16cos6°)
=sin96°/(16cos6°)
=cos6°/(16cos6°)
=1/16