The form R cos x minus alpha resources
Teach Yourself (1)

In this unit we explore how the sum of two trigonometric functions can be expressed as a single trigonometric function.
Video (2)

This mathtutor animation shows how the formula a cos x + b sin x = R cos(x-alpha) may be derived using right angled triangles. This resource is released under a Creative Commons license Attribution-Non-Commercial-No Derivative Works and the copyright is held by Skillbank Solutions Ltd.

In this unit we explore how the sum of two trigonometric functions e.g.3 cos x plus 4 sin x, can be expressed as a single trigonometric function. Having the ability to do this enables us to solve trigonometric equations and find maximum and minimum values. (Mathtutor Video Tutorial)
This resource is released under a Creative Commons license Attribution-Non-Commercial-No Derivative Works and the copyright is held by Skillbank Solutions Ltd.
Video with captions which require edits (1)

In this unit we explore how the sum of two trigonometric functions e.g.3 cos x plus 4 sin x, can be expressed as a single trigonometric function. Having the ability to do this enables us to solve trigonometric equations and find maximum and minimum values. (Mathtutor Video Tutorial)
The video is released under a Creative Commons license Attribution-Non-Commercial-No Derivative Works and the copyright is held by Skillbank Solutions Ltd.