SOH CAH TOA is a mnemonic used to remember the trigonometry ratios; sine = opposite over hypotenuse, cosine = adjacent over hypotenuse, tangent = opposite over adjacent.
Source: www.vcefurthermaths.com

n addition to sine, cosine, and tangent, there are three other trigonometric functions you need to know for the tirg: cosecant, secant, and cotangent. These functions are simply the reciprocals of sine, cosine, and tangent.
Cosecant
Cosecant is the reciprocal of sine. Its formula is:
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Secant
Secant is the reciprocal of cosine. Its formula is:
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Cotangent
Cotangent is the reciprocal of tangent. Its formula is:
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