A. 4
B. -4
C. 8
D. -8
16 cos5 θ=
If a sinx=b cosx= 2ctanx/1-tan2 x then (a2-b2)2/a2+b2=
27. Cos3 θsin5 θ=
64cos7 θ=
8sin4θ=
32cos4 θ.sin2 θ=
27 cos8 θ=
128 sin8 θ=
27 cos5 θsin3 θ=
The last terms in the expantions of sin 8θ, sin 9θ respectively are