Unit circle — Algebra II, what it means and where it is taught
The circle of radius 1 centred at the origin.
Taught in Algebra II.
Where it is taught
What it rests on
Work through these first if this one does not settle.
- Radius — Centre to edge. Half the diameter.
Practise this idea
2 questions in the course bank use Unit circle, in Radians & the Unit Circle.
Problem 1
Find sin 90°.
Worked answer
1
The point is (0,1), and sin is the y-coordinate
Problem 2
Find cos 180°.
Worked answer
-1
The point is (-1,0)
cos is the x-coordinate