Important Formula:

Sin(q) = Opposite / Hypotenuse

Cos(q) = Adjacent / Hypotenuse

Tan(q) = Opposite / Adjacent
Cotan(q)= Adjacent / Opposite
Secant(q) = 1 / cosine
Cosecant(q) = 1 / Sine

Example :

Let's saythat a = 3 , b = 4 , c = 5

Sine(q) = a / c = 3/5

Cosine(q) = b/c = 4/5

Tan(q) = a/b = 3/4

Cotan(q) = b/a = 4/3

Secant(q) = 1 / cosine(q) = 5/3

Cosecant(q)= 1 / sine(q) = 5/4

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