Prove that `cos36^0cos72^0cos108^0cos144^0=1/(16)dot`

Prove that: cos36^(@)cos72^(@)cos108^(@)cos144^(@)=(1)/(16)

Prove that (1)cos36^(@)cos72^(@)cos108^(@)cos144^(@)=(1)/(16)(2) Show that 4sin27^(@)=sqrt(5+sqrt(5))-sqrt(3-sqrt(5))

Prove that cos 36^(@) cos 72^(@) cos 108^(@) cos 144^(@)=1//16 .

Prove that cos130^@+cos110^@+cos10^@=0 .

Prove that cos65^(@)+cos115^(0)=0

Prove that: 4cos12^(0)cos48^(0)cos72^(0)=cos36^(@)

Prove that: cos78^(0)cos42^(0)cos36^(@)=(1)/(8)

Prove that: cos20^(0)cos100^(@)+cos100^(@)cos140^(@)-cos140^(@)-cos140^(@)cos200^(@)=

Prove that: cos100^(@)+cos20^(0)=cos40^(@)