In a right-angled triangle, the sides and the angles are connected by three trigonometric ratios.
The three trig ratios are:
A quick way to remember this is to memorise the word
Use the side lengths of this triangle to state the value of cosθº
Label the sides adjacent, opposite and hypotenuse in relation to the angle θº.
The side adjacent to the angle θ has length 3.
The hypotenuse has length 5.
The correct trig ratio is COS so cos θº= 3 ÷ 5
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