Trigonometric Ratios of Complementary Angles

Complementary Angles: Angles that add up to ${90^\circ }$.


Below shows right-angled △ABC.

You can shift the points B and C to change the size of △ABC.


Instructions:

1. Adjust the size of △ABC.
2. Check the boxes.
3. Observe the values of the trigonometric functions: $\sin \theta$, $\cos \theta$ and $\tan \theta$.
4. Observe the values of the trigonometric functions: $\sin \left( {90^\circ - \theta } \right)$, $\cos \left( {90^\circ - \theta } \right)$ and $\tan \left( {90^\circ - \theta } \right)$.
5. Repeat steps 1 ~ 4 for other sizes of △ABC.

Download the GeoGebra file: http://www.geogebratube.org/material/download/format/file/id/44997

Download the Worksheet: http://db.tt/y5PJ7T6P