Right-Angled Triangles (Edexcel A-Level Mathematics): Flashcards

A triangle with one angle exactly $90$ degrees.

The longest side opposite the right angle.

The side next to the angle of interest, not hypotenuse.

The side opposite the angle of interest.

$c^2 = a^2 + b^2$, where $c$ is hypotenuse.

$\sin \theta = \frac{\text{opposite}}{\text{hypotenuse}}$.

$\cos \theta = \frac{\text{adjacent}}{\text{hypotenuse}}$.

$\tan \theta = \frac{\text{opposite}}{\text{adjacent}}$.

Area = $\frac{1}{2} \times \text{base} \times \text{height}$.

Area = $\text{length} \times \text{width}$