formulas of trignometryand how can we solve

Hi Mohammad

I can provide you with the link of trigonometric identities and equations but I'd suggest you make a small notebook of these identities and note them down on your own from any good book such as R.D Sharms or R.S Agarwal. It will help you learn the identities.As for the question solving part, once you learn these identities and solve solved questions from different books, you'll start understanding how to solve these questions and will understand how to use different identities in the questions and solve them easily. The link to the identities:

https://www.learncbse.in/trigonometry-formulas/