Prove that `(sin36^(@))/(cos54^(@))+(cos36^(@))/(sin54^(@))=2`

Prove that (sin36^(@)+cos36^(@))/(cos54^(@)+sin54^(@))=1

cos54^(@)cos36^(@)-sin54^(@)sin36^(@)=0

Evalute (f) (sin36^(@))/(cos54^(@))-(sin54^(@))/(cos36^(@))

Show that cos 36^(@) cos 54 ^(@) -sin 36^(@) sin 54^(@) =0

Show that cos 36^(@) cos 54 ^(@) -sin 36^(@) sin 54^(@) =0

Show that cos 36^(@) cos 54 ^(@) -sin 36^(@) sin 54^(@) =0

Show that cos 36^(@) cos 54 ^(@) -sin 36^(@) sin 54^(@) =0

Show that cos 36^(@) cos 54 ^(@) -sin 36^(@) sin 54^(@) =0

sin36^(@)+cos36^(@)=sqrt(2)cos9^(@)

Prove that (i) sin 70^(@) cos 10^(@) -cos 70^(@) sin 10^(@) =(sqrt(3))/(2) (ii) cos 50^(@) cos 10^(@) -sin 50^(@) sin 10^(@) =(1)/(2) (ii) cos 80^(@) cos 20^(@) + sin 80^(@) sin 20^(@) =(1)/(2) (iv) sin 36^(@) cos 9^(@) + cos 36^(@) sin 9^(@) =(1)/(sqrt(3))