6.3 · Non-right-angled trianglesLesson 1 of 15Free preview
Sine and cosine of obtuse angles
Past 90° the sine stays positive and the cosine turns negative: sin 150° = sin 30°.
6.3 · Non-right-angled trianglesLesson 1 of 15Free preview
Past 90° the sine stays positive and the cosine turns negative: sin 150° = sin 30°.