U substitution with trig sine and cosine

The video tutorial explains the process of taking derivatives of sine functions, focusing on the transition from sine to cosine. It introduces the concept of U-substitution, using sine of 3X as an example, and discusses the need to adjust the derivative by multiplying with a constant. The tutorial concludes with the integration process, replacing variables, and finalizing the solution.

What expression does the teacher derive when integrating the function?

What final result does the teacher mention after integration?