Syntax
COT(number)
| Parameter | Description |
|---|---|
| number | Parameter of the COT function. |
Examples
Cotangent of 45 degrees
Formula
=COT(PI()/4)
Returns 1. COT(45°) = 1/TAN(45°) = 1/1 = 1. At 45°, tangent and cotangent are equal.
Cotangent of 30 degrees
Formula
=COT(RADIANS(30))
Returns ~1.732 (√3). COT(30°) = COS(30°)/SIN(30°) = (√3/2)/(1/2) = √3.
Using with engineering formula
Formula
=PI()*COT(PI()*0.3)
Returns ~1.376. The digamma function and other special functions involve π×COT(πx) terms.
Common Errors
#DIV/0!
COT(0) = 1/TAN(0) = 1/0, which is undefined. Any multiple of π gives #DIV/0!.
#VALUE!
Non-numeric arguments return #VALUE!.
Tips
Reciprocal of TAN
COT(x) = 1/TAN(x) = COS(x)/SIN(x). If you already have TAN, you can just use 1/TAN instead of COT.
Undefined at 0 and π
COT is undefined where SIN equals zero: at 0, π, 2π, etc. These inputs produce #DIV/0!.
Less common but important
COT appears in Fourier series, heat equation solutions, and impedance calculations. If your engineering formula calls for it, use it directly rather than 1/TAN for clarity.
Try COT in Viztab
Import your data and use COT with 370+ other formulas. No signup required.
Open Viztab