We can derive reduction formulae for the integral of the form ${\int }_{ }^{ }{\sin }^{n}xdx,{\int }_{ }^{ }{\cos }^{n}xdx,{\int }_{ }^{ }{\tan }^{n}xdx$${\int }_{ }^{ }{\cot }^{n}xdx$and other integrals of these form using integration by parts. In turn these reduction formulae can be used to compute integrals of higher power of $\sin x,\cos xetc$