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COS()

Overview

COS() calculates the cosine of an angle specified in radians. The cosine function returns a value between -1 and 1, representing the ratio of the adjacent side to the hypotenuse in a right triangle. This function is commonly used in trigonometric calculations, geometry, and physics.

Function Format

COS(number)

Return Value

COS() returns a numeric value between -1 and 1

Examples

COS(0)        = 1       (cosine of 0 radians)
COS(PI())     = -1      (cosine of π radians)
COS(PI()/2)   = 0       (cosine of π/2 radians)
COS(100)      = 0.8623  (cosine of 100 radians)
COS(PI()/4)   = 0.7071  (cosine of π/4 radians)
COS(PI()/3)   = 0.5     (cosine of π/3 radians)
COS(2*PI())   = 1       (cosine of 2π radians)

Notes

• The input angle must be in radians, not degrees.
• To convert degrees to radians, multiply by (π/180).
• The result is always between -1 and 1, inclusive.
• Common values:
  • COS(0) = 1
  • COS(π/2) = 0
  • COS(π) = -1
  • COS(2π) = 1
• This function is commonly used in:
  • Trigonometric calculations
  • Geometry and physics problems
  • Wave and oscillation calculations
  • Signal processing
• The function is periodic with a period of 2π radians.

See Also

• SIN()
• TAN()
• ACOS()
• PI()