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Calculates the arc cosine (inverse cosine) of a number, which is the angle in radians whose cosine is the specified number.

See also:


SELECT ACOS(value) FROM <multipartIdentifier>;


A numeric expression within the range of -1 to 1, inclusive, for which the arc cosine is to be calculated.

Return Value(s)

Returns the arc cosine of the specified value in radians.


Calculate the arc cosine of 0.5

SELECT ACOS(0.5) AS arc_cosine_value;

This query returns approximately 1.047, as the arc cosine of 0.5 radians is π/3, which is about 1.047 radians.

Calculate the arc cosine of 1

SELECT ACOS(1) AS arc_cosine_value;

This query calculates the arc cosine of 1, resulting in 0, since the cosine of 0 radians is 1.