Circular motion
Unit circle
Quadrant I
1
−1
1
−1
(0.707, 0.707)
The circle becomes a wave
See trigonometry
come alive.
Drag the point around the unit circle and watch its coordinates trace the sine, cosine, and tangent graphs.
Linear motion
Live graph
1
−1
0
π/2
π
3π/2
2π
Angle
\(45^\circ\)
\(\frac{\pi}{4}\,\mathrm{rad}\)
sin
Vertical height
\(\frac{\sqrt{2}}{2}\)
\(\approx 0.707\)
cos
Horizontal distance
\(\frac{\sqrt{2}}{2}\)
\(\approx 0.707\)
tan
Slope
\(1\)
\(=1.000\)
\(45^\circ\)