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Curated by: Khan Academy India - English (9 videos)
https://www.khanacademy.org/math/ncert-class-10 Let's try to prove a trigonometric identity involving Secant, sine, and cosine of an angle to understand how to think about proofs in trigonometry. There are many ways to prove these identities. Created by Aanand Srinivas. Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now! Khan Academy India is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We have videos and exercises that have been translated into multiple Indian languages, and 15 million people around the globe learn on Khan Academy every month. Support Us: https://india.khanacademy.org/donate