This article was previously published under Q188075
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Microsoft Excel has built-in functions for a large number of trigonometricfunctions, but does not include all such functions. However, those notincluded may be derived from existing functions by using a formula inMicrosoft Excel.
Some functions that may be derived from built-in Excel functions include:
secant (SEC) cosecant (CSC) cotangent (COT)
These functions are the inverse of the cosine, sine, and tangent,respectively. To calculate these additional functions where "angle" is themeasure of the angle in radians, use the following formulas:
SEC(angle) = 1/COS(angle)
CSC(angle) = 1/SIN(angle)
COT(angle) = 1/TAN(angle)
For example, to find the cotangent of a 30 degree angle, use the followingformula:
NOTE: To convert an angle from degrees to radians, multiply the angle indegrees by PI()/180.
NOTE: Trigonometric functions in Excel must use angles measured in radiansrather than in degrees.
For additional information on converting degree angles to radians, pleasesee the following article in the Microsoft Knowledge Base: