 Hi and welcome to the session. Let us discuss the polyquestion. The question says proof that integral of log 1 plus tan theta from 0 to pi by 4 is equal to pi by 8 log 2. Let's now begin with the solution. Let i is equal to integral of log 1 plus tan theta from 0 to pi by 4. We know that integral of fx from 0 to a is equal to integral of minus x from 0 to a. So by using this property i is equal to integral of log 1 plus 4 minus theta from 0 to pi by 4 is equal to tan b divided by using this formula from 0 to integral of 0 to pi by 4 minus integral of lower than 0 to pi by 4.