Inverse Cosine Calculator
Calculate the inverse cosine (arccos) of a value. Input a number between -1 and 1 to get the angle in degrees or radians.
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How to use this tool?
How to Use the Inverse Cosine Calculator
- Enter a value (x) between -1 and 1 in the "Value (x)" field. This is the cosine of the angle you want to find.
- Select the output unit: choose Degrees or Radians from the dropdown.
- Click the Calculate button (or press Enter).
- The result shows the arccos(x) (the angle whose cosine is x) in your chosen unit, with up to 6 decimal places.
- A formula summary displays the input and computed angle for reference.
Note: The input must be between -1 and 1 inclusive. If you enter an invalid number, an error message will appear.
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Frequently Asked Questions
Inverse cosine, also known as arccos, is the inverse function of cosine. It returns the angle whose cosine is a given number.
The input must be a number between -1 and 1 inclusive.
Yes, you can select either degrees or radians as the output unit.
