Applications of Trigonometric Functions (Grade 12 NSC Matric Mathematics): Flashcards

$\frac{1}{2}bc \sin A$

Two sides & included angle; no perpendicular height given

$\frac{a}{\sin A} = \frac{b}{\sin B} = \frac{c}{\sin C}$

Two angles & one side OR two sides & opposite angle

$a^2 = b^2 + c^2 - 2bc \cos A$

Two sides & included angle OR all three sides

Area rule for area; cosine rule for third side/angle

$\sin C$ gives both acute & obtuse solutions; check which fits

Draw diagram; identify triangles; apply trig rules step by step

...the largest angle