Arccos Calculator

arccos
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Angle in degrees:
°
Angle in radians:
rad
Calculation:

Arccos Calculator

An online calculator to calculate the inverse cosine function arccos(x) in radians and degrees.Use arccos calculator to easily calculate the arccosine of a number. Supports input of either decimal numbers (e.g. 0.5, -0.5) or fractions (e.g. 1/2, -1/2).

Arccos definition

The arccosine function is the inverse function of cos(x).

arccos(x) = cos^-1(x)

For example, If the cosine of 60° is 0.5:

cos(60°) = 0.5

Then the arccos of 0.5 is 60°:

arccos(0.5) = cos^-1(0.5) = 60°

How to use the arccos (x) calculator?

Enter x as a real number, within the domain of arccos function such that -1 ≤ x ≤ 1 and the number of decimal places desired then press "enter". Two answers are displayed: one in radians and the second in degrees.

What is the inverse of cosine (arccos)?

Arccos is the inverse of a trigonometric function - specifically, the inverse of the cosine function. However, as trigonometric functions are periodic, then, in a strict sense, they cannot be inverted. We can deal with that problem by choosing an interval in which the basic function is monotonic. You can pick many different ranges, but for cosine the common choice is [0,π]. This range is called the set of principal values.

Arccos(x) is the most commonly used notation, as cos^-1x may be misleading - remember that inverse cosine is not the same as the reciprocal of the function (in other words, raising to the power -1):

cos^-1x ≠ 1/cos(x)

Arccos function :- The arccos (arcus cosine, arccosine) is one of the inverse trigonometric functions (antitrigonometric functions, arcus functions) and is the inverse of the cosine function. It is sometimes written as cos^-1(x), but this notation should be avoided as it can be confused with an exponent notation (power of, raised to the power of). The arccos is used to obtain an angle from the cosine trigonometric ratio, which is the ratio between the side adjacent to the angle and the hypotenuse in a right triangle.

The function spans from -1 to 1, and so do the results from our arccos calculator. The range of the angle values is usually between 0° and 180°. There are a number of arccos rules, like that cos(arccos(x)) = x, or that arccosα + arccosβ = arccos(αβ - √((1-α²)(1-β²)), as well as sine of the arccosine: sin(arccos(x)) = √(1-x²), which can help you in trigonometry calculus.