On page 95, a proof of the orthogonality of Legendre polynomials is discussed. Reconstruct the proof with detailed steps, using the weighted integral formulation for Legendre polynomials. Instructions: Stick to solving the problem only. Provide a clear outline, detailed steps, and all necessary calculations. Do not add irrelevant content. Link: [https://drive.google.com/file/d/1wKSrun-GlxirS31Z9qoHazb9tC440 AZF/view?usp=sharing]