 Hi and welcome to the session. I am Purva and I will help you with the following question. Integrate the function cos x upon under root of 4 minus sin square x. Now we start with this solution. So we denote this function by i. So we have i is equal to integral cos x upon under root 4 minus sin square x dx. We mark this as equation one. Now we put sin x is equal to t. So we have put sin x is equal to t. Now differentiating we get, differentiating sin x we get cos x dx is equal to differentiating t we get dt. So we have cos x dx is equal to dt. Putting these values in one we get therefore i is equal to integral. Now cos x dx is equal to dt. So we have dt upon under root 4 minus. Now we have sin x is equal to t. So sin square x is equal to t square. So we have minus t square. This is equal to integral dt upon under root 2 square minus t square. Now we know a formula that integral dx upon under root of a square minus x square is equal to sin inverse x by a plus c. So by taking x is equal to t and a is equal to 2 we get this is equal to sin inverse t by 2 plus c right. Now we have put sin x is equal to t. So we have this is equal to sin inverse in sin x by 2 plus c since sin x is equal to t. So we get our answer as sin inverse sin x upon 2 plus c. So this is the answer of the question. Hope you have understood the solution. Take care and bye.