The trigonometric ratios sine, cosine and tangent are used to calculate angles and sides in right angled triangles. We are now going to extend trigonometry beyond right angled triangles and use it ...

Sine, cosine and tangent all have different positive or negative values depending on what quadrant they are in. Calculating the area of a triangle using trigonometry Trigonometry can be used to ...

Any attempt at using sine, cosine, or tangent to verify Pythagoras’ equation seemed destined to rely on the theorem itself, leading to a circular argument. But two high school students refused ...