f(x)=∫dxsin4x is a
Polynomial of degree 3 in cot x
Polynomial of degree 4 in cot x
Polynomial of degree 4 in sin x
Polynomial of degree 3 in tan x
f(x)=∫1+cot2xcosec2xdx=−cotx+13cot3x+C
which is polynomial of degree 3 .