Trigonometry Proof: cos (x + y) = cos x cos y – sin x sin y ( скачать в хорошем качестве

Trigonometry Proof: cos (x + y) = cos x cos y – sin x sin y (

Trigonometry Proof: cos (x + y) = cos x cos y – sin x sin y TRIGONOMETRIC FUNCTION PRACTICE QUESTIONS-    • TRIGONOMETRY IIT JEE MAINS, JEE ADVANCED E...   BINOMIAL TOUGH PRACTICE QUESTIONS -    • Binomial Theorem TOUGH AND TRICKY QUESTION...   MANY MORE ARE THERE IN THE PLAYLIST. PLEASE PLEASE CHECK ONCE. YOU WILL BE AMAZED TO SEE THE QUESTIONS. https://www.mathsphy.com In all these videos on Trigonometric Functions I have always focused on explaining the basics and then solving the questions. My way of solving question will always refer back to the basics explained previously so that students can make the connect between basics and application of them. Lets start: Arc/ Angle and Radian Relation between Degree and Radian Radian measure/ Degree measure If x increase or decreases by the integral multiple of 2\mathbit{\pi}, the value of sine or cosine functions do not change sin(2n\mathbit{\pi} + x) = sinx , n \in Z cos(2n\mathbit{\pi} + x) = cosx , n \in Z cos x = 0, if x = 0, \pm\mathbit{\pi}/2, \pm\mathbf{3}\mathbit{\pi}/2, \pm\mathbf{5}\mathbit{\pi}/2,……i.e.., when x is an odd multiple of \mathbit{\pi}/2 . cos x = 0 implies x = (2n + 1) \frac{\mathbit{\pi}}{\mathbf{2}}, where n is an integer sin x = 0, if x = 0, \pm\mathbit{\pi}, \pm\mathbf{2}\mathbit{\pi}, \pm\mathbf{3}\mathbit{\pi},……i.e.., when x is an integral multiple of \mathbit{\pi} . Sin x = 0 implies x = n\mathbit{\pi}, where n is an integer Sign of Trigonometric Functions Cos (x + y) = cos x cos y – sin x sin y Principal Solutions General Solutions Principal Solutions: Given x value has solutions which are less than 2\mathbit{\pi} and more than or equal to 0, those solutions are called principal solutions: Sets, Relations and Functions, Trigonometric Functions, Permutations and Combinations, Linear Inequality, Binomial Theorem, Straight Lines, Conic Sections. Find us on youtube    / mathsphy   Find us on Facebook:   / www.mathsphy   Contact: Abhishek Agarwaal +91 7317769273 abhishek@mathsphy.com abhishekagrawal776@gmail.com https://www.udemy.com/share/100amK/ Prove that: Cos (x + y) = cos x cos y – sin x sin y Mathsphy www.mathsphy.com