acos domain
The C++
acos()
function returns the the inverse cosine of a number in radians. It is defined in <cmath> header file.
Syntax
acos(x);
Parameters
The acos()
function takes a one argument in the range [-1, 1]
, means the value of cosine is in the range of 1
and -1
.
acos
Return value
The argument is in the range [-1, 1],
acos()
function returns the value in the range of[0, π]
.
std acos
acos() prototype [As of C++ 11 standard]
double acos(double x); float acos(float x); long double acos(long double x); double acos (T x); // For integral type
Example 1: C++ acos()
#include <stdio.h> #include <math.h> #define PI 3.14159265 int main () { double param, result; param = 0.1; result = acos(param) * 180.0 / PI; printf ("The arc cosine of %f is %f degrees.\n", param, result); return 0; }
Output
The arc cosine of 0.100000 is 84.260830 degrees.
acos function
Example 2 : C++ acos() ( Argument greater than 1 )
If the argument is greater than
1
or less than-1
,acos()
returns NaN i.e. not a number.
#include <stdio.h> #include <math.h> #define PI 3.14159265 int main () { double param, result; param = 4.4; result = acos(param) * 180.0 / PI; printf ("The arc cosine of %f is %f degrees.\n", param, result); return 0; }
Output
- The Above Code returns NaN (Not a Number)
The arc cosine of 4.400000 is nan degrees.