The Cosine Rule (VCE SSCE General Mathematics): Quizzes

Any triangle

The third side

$c^2 = a^2 + b^2 - 2ab \cos C$

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

It becomes Pythagoras' theorem

Side $9$

$A$ is obtuse (between $90°$ & $180°$)

As three-figure numbers (e.g., $037°$)

DEGREE mode

Two sides and the included angle