Evaluate the following integrals:

(i)

(ii)

(i)

⇒

Now, we know that 1+cosx=2cos² (x/2)

So, applying this identity in the given integral, we get,

⇒

Ans:

ii)

⇒

Now, we know that cosec²x-cot² x=1

So, applying this identity in the given integral we get,

⇒

⇒

⇒

⇒-2cotx-x+c

⇒-2cotx-x+c

Ans: -2cotx-x+c