Trigonometric ratios

You can use Pythagoras’ theorem to solve problems in three dimensions: In a right-angled triangle the sides and the angles are related by three trigonometrical ratios: the sine (abbreviated to sin), the cosine (abbreviated to cos) and the tangent (abbreviated to tan).

To use these remember that you need to identify which side is the hypotenuse (the longest side), which is the opposite (opposite the given angle), and which is the adjacent (next to the given angle), thus:

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