How to apply u substitution to a rational function

The video tutorial explains the concept of u-substitution in calculus, focusing on identifying the 'u' in integrals and applying the method to solve them. The instructor corrects an error in the derivative calculation and demonstrates the integration process using u-substitution. The tutorial concludes with a discussion on possible variations of the solution.

How do you integrate the expression U to the negative second divided by -2?

What is the significance of adding C after integrating?