This key facts covers The Values You MUST Know within Exact Trig Values for GCSE Mathematics. Revise Exact Trig Values in Geometry & Measures for GCSE Mathematics with 14 exam-style questions and 4 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 2 of 7 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
The Values You MUST Know
| Angle | sin | cos | tan |
|---|---|---|---|
| 0° | 0 | 1 | 0 |
| 30° | 1/2 | √3/2 | 1/√3 = √3/3 |
| 45° | 1/√2 = √2/2 | 1/√2 = √2/2 | 1 |
| 60° | √3/2 | 1/2 | √3 |
| 90° | 1 | 0 | undefined |
Practice questions for Exact Trig Values
What is the exact value of sin 30°?
James says that sin 30° and cos 60° are equal. Is James correct? Explain your answer using exact values.
Quick recall flashcards
Cos Pattern
Cos is sin BACKWARDS. cos θ = sin(90°-θ). So cos 30° = sin 60°, etc.
Sin Pattern
sin 0°=0, sin 30°=1/2, sin 45°=√2/2, sin 60°=√3/2, sin 90°=1. Pattern: √n/2 for n=0,1,2,3,4