6.3 · Non-right-angled trianglesLesson 2 of 15Free preview
Finding an obtuse angle from its sine or cosine
One sine gives two angles, x and 180° − x. A negative cosine always means an obtuse angle.
6.3 · Non-right-angled trianglesLesson 2 of 15Free preview
One sine gives two angles, x and 180° − x. A negative cosine always means an obtuse angle.