What is the input range?

arccos is defined for values between -1 and 1 (inclusive). Outside this range the result is not a real number.

What is the output range?

arccos returns angles from 0° to 180° (0 to π radians).

Inverse cosine: enter a value from -1 to 1 to get the angle in degrees. arccos(x) = angle whose cosine is x.

Value (-1 to 1)

What is the input range?: arccos is defined for values between -1 and 1 (inclusive). Outside this range the result is not a real number.
What is the output range?: arccos returns angles from 0° to 180° (0 to π radians).

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