Geometry (Trigonometrical Identities) Ultimate revision guide for Further maths GCSE

Ultimate Guide to Further maths GCSE Geometry (Trigonometrical Identities) (level 2 Qualification from AQA)
3. Coordinate Geometry

[crookshanks]

Very well made and easy to follow, thanks a bunch!

[alphadron]

Slight error in Q1, you said that cos pheter is obtuse but it said that sin pheter is the obtuse angle. I don’t think you can have 2 obtuse angles in that equation

[amberwhite]

In your topic test on this and Trigonometrical Equations, for the first question you went from sin^x/cos^x - 1 and then wrote sin^x - cos^x/cos^x. Why did the -1 become a "-cos^x" and not a "-cos^x -sin^x"