Li Yinan

Welcome to my new website. Introduction And My Vision First of all, thanks for visiting Lya’s website. I mainly use it to post about my life and personal thoughts. I’d also like to use it to meet...

Problem Setup let’s try to solve an easy integral. $ \int_{0}^{\frac{\pi}{2}} \frac{1}{1+sint} dt $ The traditional method is to substitute $x=tan\frac{t}{2}$ to solve the problem. Preperations B...