Question

Integrate: ∫(cos^3⁡ x)^2 dx

Answer 1

∫cos^6 x dx

note:
∫cos^n dx=[cos^(n-1)x /n sin x]+(n-1)/n ∫cos^(n-2)x dx

and
∫cos^2 x dx = x/2 + sin 2x /4