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Math Library (libm, -lm)

#include <complex.h>

The
`cacos()`,
`casin()`,
and
`catan()`
functions compute the principal value of the inverse cosine, sine,
and tangent of the complex number
z,
respectively.
The
`cacosh()`,
`casinh()`,
and
`catanh()`
functions compute the principal value of the inverse hyperbolic
cosine, sine, and tangent.
The
`cacosf()`,
`casinf()`,
`catanf()`
`cacoshf()`,
`casinhf()`,
and
`catanhf()`
functions perform the same operations in
float
precision.
The
`cacosl()`,
`casinl()`,
`catanl()`
`cacoshl()`,
`casinhl()`,
and
`catanhl()`
functions perform the same operations in
long, double
precision.

There is no universal convention for defining the principal values of these functions. The following table gives the branch cuts, and the corresponding ranges for the return values, adopted by the C language.

Function | Branch Cut(s) | Range |

cacos | (-∞, -1) [cu] (1, ∞) | [0, π] |

casin | (-∞, -1) [cu] (1, ∞) | [-π/2, π/2] |

catan | (-∞*I, -I) [cu] (I, ∞*I) | [-π/2, π/2] |

cacosh | (-∞, 1) | [-π*I, π*I] |

casinh | (-∞*I, -I) [cu] (I, ∞*I) | [-π/2*I, π/2*I] |

catanh | (-∞, -1) [cu] (1, ∞) | [-π/2*I, π/2*I] |

These functions conform to
ISO/IEC 9899:1999 ("ISO C99").

CACOS (3) | February 15, 2017 |

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