There are many ways that allow you to work out the values for the trigonometric ratios of the most common angles (0°, 30°, 45°, 60°, and 90° ). Here is one of them.

A final Note….

The above did not address the 3rd trigonometric ratio – Tangent. However given that we know that tan (θ) = sin( θ ) / cos( θ ); then we can use the above method to work out the tangent of these angles.

Rationalise the Denominator
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