Up to 90°
On this first applet, control the angle to see how the red, green and blue lines get longer or shorter.
- At what angle do the green and red line segments have equal length?
- Given that the angle permitted ranges from zero to 90°, whats the shortest/longest green line segment?
- What’s the shortest/longest red line segment?
- What’s the shortest/longest blue line segment?
- How many right angled triangles are there in the diagram?
- What does Pythagoras’ theorem say about those right angled triangle(s)?
Matching to 90°
- Level 1 – use the applet with values
- Level 2 – use the applet without values
- Level 3 – visualize the applet with the mind’s eye
0 to 360 degrees
However sine, cosine and tangent are defined for any angle – from negative infinity to positive infinity. Here we see the value of sine, cosine and tangent for angles between 0° and 360°.
Matching, 0 – 360
Once again, by considering the visual above, match the labels with their values: