Double Angle Identities - Trigonometry - Socratic
Learn how to use double angle identities to solve equations, find exact values, and simplify expressions involving sin, cos, and tan. See examples, explanations, and proofs of the identities.
What is difference between 2cosx and cos2x? - Socratic
May 16, 2018 · Learn how to distinguish between 2cosx and cos2x, two different trigonometric functions. See the formulas, examples and explanations for cos(2x) and cos(3x) and avoid common mistakes.
How do you solve cos2x= cosx from 0 to 2pi? - Socratic
Apr 11, 2016 · Use the identity: #cos 2x = 2cos^2 x - 1#.The given equation transforms to: #2cos^2 x - cos x - 1 = 0#. Solve this quadratic equation for cos x.
Proving Identities - Trigonometry - Socratic
Learn how to prove trigonometric identities involving sinx, cosx, tanx, cotx, secx and cscx. See examples, explanations and questions with solutions on Socratic.
How do you prove cos2x=cos^2x-sin^2 using other trigonometric ...
Dec 17, 2015 · Learn two methods to derive the double angle identity for cosine from the angle-sum identity and De Moivre's theorem. See explanations, examples and answers from trigonometry experts on Socratic.
Fundamental Identities - Trigonometry - Socratic
The best videos and questions to learn about Fundamental Identities. Get smarter on Socratic.
What is cosx times cos2x? - Socratic
Aug 15, 2016 · What is cosx times cos2x? Trigonometry Trigonometric Identities and Equations Fundamental Identities. 1 ...
How do you prove cos2x = 2cos^2x -1? - Socratic
May 24, 2015 · Learn how to use the identity cos (a + b) = cos a.cos b - sin a.sin b to derive the double angle formula cos 2x = 2 cos2 x - 1. See the answer and the steps with examples on Socratic.
How do you find the general solutions for #sinx = cos2x#?
Sep 18, 2015 · Find the general solutions for sin x = cos 2x using trigonometric identities and quadratic equations. See two answers with explanations and diagrams on Socratic.
How do you solve cos2x = sinx on the interval 0 <= x<= 2pi?
Apr 16, 2015 · How do you solve #cos2x = sinx# on the interval #0 <= x<= 2pi#? Trigonometry Trigonometric Identities and Equations Solving Trigonometric Equations