Arc sine function
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Contents  |
|
Interface
#include <math.h>
| double | asin (double x) |
| long | asinl (long double x) |
| float | asinf (float x) |
#include <complex.h>
| complex | asin (complex x) |
| double complex | casin (complex x) |
| float complex | casinf (float complex x) |
| long double complex | casinl (long double complex x) |
Description
The
asin function computes the principal value of the arc sine of
x in the range
![[-1,1]](/images/eqns/b7e6dc82a834272acb8ebe9b7a230280.gif)
,
returning a value in the interval
![[-\pi/2,+\pi/2]](/images/eqns/153997bc2115b3ad8e10bfe92d8088b8.gif)
. The arc sine is also often called the inverse sine and is denoted by

.
The complex inverse sine is defined by:
Example 1:
#include <stdio.h>
#include <math.h>
int main(void)
{
double result, x = 0.289;
result = asin(x);
printf("The arc sin of %lf is %lf\n", x, result);
return 0;
}
Output:
The arc sin of 0.289000 is 0.293182
Special Values
asin (
0 ) returns 0.
asin (
x ) returns a NaN and raises the invalid floating-point exception for |x| > 1.
See Also
acos,
atan,
atan2,
cos,
cosh,
sin,
sinh,
tan,
tanhStandards
The
asin function conforms to ISO/IEC 9899:1999(E).
Compatibility
| DOS | UNIX | Windows | ANSI C | C++ only |
| asinl | • | | • | | |
| asinf | • | • | • | | |
| Real asin | • | • | • | • | |
| Complex asin | • | | • | | • |
| Complex casin | | • | | | • |
Last Modified: 2009-04-23 08:22:26 Page Rendered: 2010-03-14 21:13:24