There are three main trigonometric functions - Sine θ (sin θ), Cosine θ (cos θ) and Tangent θ (tan θ). Sin θ - Ratio of Perpendicular to Hypotenuse Cos θ - Ratio of Base to Hypotenuse Tan ...

Fundamentally a trigonometric table must describe three ratios of a right triangle. So we throw away sin and cos and instead start with the ratios b/l and d/l. The ratio which replaces tan would ...

As the numbers are known on the opposite and the hypotenuse, then we look for the ratio which uses both these sides (SOH CAH TOA). That ratio is the sine ratio. \(\sin (x^\circ ) = \frac{{opposite} ...

Label the sides of the triangle \(o\), \(a\) and \(h\). Next choose the correct ratio from \(s^o_h~c^a_h~t^o_a\). The length \(h\) is known and the length \(o\) must be calculated. Label the sides ...

Interestingly enough, the trigonometric functions that define those relationships are also closely tied to circles. Needless to say, this makes trig one of the hardest topics in math for students ...