The acos() method returns the arccosine of a number as a value value between 0 and PI radians.
Note: If the parameter x is outside the range -1 to 1, the method will return NaN.
Tip: -1 will return the value of PI.
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The acos() method is supported in all major browsers.
| Parameter | Description |
|---|---|
| x | Required. A number |
| Type | Description |
|---|---|
| Number | A Number, from 0 to PI, or NaN if the value is outside the range of -1 to 1 |
| JavaScript Version: | 1.0 |
|---|
JavaScript Math Object
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