Dr. J's Maths.com
Where the techniques of Maths
are explained in simple terms.

Trigonometry - Measuring angles.
Main page.

 The following topics are linked from this page: 1. The basic trigonometric ratios and their relationships. 2. Angles of any magnitude (i.e. around the circle). 3. Finding a trig ratio given another. 4. Trigonometric identities. 4. Trigonometric equations. 5. Sine and Cosine rules. 6. Angles of elevation and depression. 7. Bearings. 8. Radial surveys. 9. 3-D trigonometry. 10. Radians. 11. Mensuration (arc length, area of sectors, etc).

 Definition of the basic trigonometric ratios. History of the basic relationships and their meaning. Determining a ratio - Test Yourself 1. Determining a ratio - Test Yourself 1 - Solutions. The basic relationships. Summary of the basic relationships - for reference and for helping you learn them. Trig relationships - Test Yourself 1. Trig relationships - Test Yourself 1 - Solutions. Finding a side in a triangle - Test Yourself 1. Finding a side in a triangle - Test Yourself 1 - Solutions. Finding an angle in a triangle - Test Yourself 1. Finding an angle in a triangle - Test Yourself 1 - Solutions. Angles of any magnitude. Angles in quadrants - Test Yourself 1. Angles in quadrants - Test Yourself 1 - Solutions. Finding a trig ratio given the value of another ratio. Overview of main steps with an example. Ratio to ratio - Test Yourself 1. Ratio to ratio - Test Yourself 1 - Solutions. Trigonometry identities. See Equations and identities - Main page. Further trigonometric identities. See Equations and identities - Main page. Solving trigonometric equations (angles in degrees). See Equations and identities - Main page. Sine and Cosine Rules. Sine and Cosine Rules - Introduction - similarities and differences. Sine Rule. Overview of steps for using the Sine Rule. Sine Rule - Test Yourself 1. Sine Rule - Test Yourself 1 - Solutions. Sine Rule - Test Yourself 2. Sine Rule - Test Yourself 2 - Solutions. Cosine Rule Overview of steps for using the Cosine Rule. Cosine rule - Test Yourself 1. Cosine rule - Test Yourself 1 - Solutions. Using the cosine rule to approximate the value of π. Area of a triangle. Angles of elevation and depression. General introduction to the concepts. Elevation & depression - Test Yourself 1. Elevation & depression - Test Yourself 1 - Solutions. Bearings. General introduction. Bearings - Test Yourself 1. Bearings - Test Yourself 1 - Solutions. Bearings and Trig. Rules - Test yourself 1. Bearings and Trig. Rules - Test yourself 1 - Solutions. Radial surveys Radial surveys - Test Yourself 1. Radial surveys - Test Yourself 1 - Solutions. 3-dimensional trigonometry. Radians What are radians? Radians - Test Yourself 1. Radians - Test Yourself 1 - Solutions. Mensuration (arc length and areas). Arc length and sectors - Test Yourself 1. Arc length and sectors - Test Yourself 1 - Solutions. Arc length and sectors - Test Yourself 2.