 Hi and welcome to the session. I'm Priyanka and let us do the following question together. Say find the values of the trigonometric function cot minus 15 pi by 4. So let us start. Now here we are given cot. Cot is a reciprocal of tan x, right? So it will repeat itself after an interval of pi, right? As it is done with tan also. So here we can write cot minus 15 pi by 4 and we can add a larger number to it so as to make it positive that is a multiple of pi only. Now the multiple of pi which is greater than minus 15 pi by 4 will be 4 pi and the value will come out to be cot pi by 4. Now the value of cot pi by 4 will be reciprocal of the value of tan pi by 4. Since tan pi by 4 is 1 so that means cot pi by 4 will also be 1. So this becomes the answer of the question that was needed to be solved. I hope you enjoyed this session and do remember when your x is given to you as negative and a larger number that is a multiple of the interval to it and after simplification write the value that is known to you. Bye for now.