In mathematics, the inverse trigonometric functions are the inverse functions of the trigonometric functions. The principal inverses are listed in the following table.If x is allowed to be a complex number, then the range of y applies only to its real part.The notations sin−1, cos−1, etc are often used for arcsin, arccos, etc, but this notation causes confusion, e.g. between arcsin(x) and 1/sin(x).
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