How to solve trigonometric equations with negative angles

Solve trigonometric equations that have negative angles. Here I show you how to use the quadrant rule or CAST diagram to solve trigonometric equations where the angle ranges are negative. It saves having to use trigonometric graphs and so makes a solution quicker and more efficient. YOUTUBE CHANNEL at https://www.youtube.com/ExamSolutions EXAMSOLUTIONS WEBSITE at https://www.examsolutions.net/ where you will have access to all playlists covering pure maths, statistics and mechanics. FACEBOOK: https://www.facebook.com/examsolutions.net/ NEW INSTAGRAM: https://www.instagram.com/examsolutionsguy/ TWITTER: https://twitter.com/ExamSolutions THE BEST THANK YOU: https://www.examsolutions.net/donation/