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acos() : Arccosine (Inverse Cosine)

Calculate the arccosine (inverse cosine) of a value, returning the angle in radians.

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acos(value)

Parameters

Parameter Type Required Description
value Number Yes Value between -1 and 1

Returns

Type: Double

The angle in radians (between 0 and π).

Examples

Basic Arccosine

<p>acos(0.5) = {{format(acos(0.5), '0.000')}} radians</p>
<p>acos(0.5) = {{format(degrees(acos(0.5)), '0.0')}}°</p>

Output:

<p>acos(0.5) = 1.047 radians</p>
<p>acos(0.5) = 60.0°</p>

Find Angle from Adjacent Side

<p>Angle: {{format(degrees(acos(model.adjacent / model.hypotenuse)), '0.0')}}°</p>

Data:

doc.Params["model"] = new {
    adjacent = 8.66,
    hypotenuse = 10
};

Output:

<p>Angle: 30.0°</p>

Notes

  • Value must be between -1 and 1
  • Returns angle in radians
  • Result range: 0 to Ï€
  • Inverse of cos() function
  • For degrees, use: degrees(acos(value))

See Also