What is sin() in C?

The sin() function in C returns the sine of a number. To be more specific, it returns the sine of a number in the radians float value.

The illustration below shows the mathematical representation of the sin() function.

Syntax

double sin(double num)

Parameter

This function requires a number that represents an angle in radians as a parameter.

In order to convert degrees to radians, use the following formula:

radians = degrees * ( PI / 180.0 )

Return value

sin() returns the sine of a number (radians float value) that is sent as a parameter.

Example

#include<stdio.h>
//header file
#include<math.h>

int main() {
    //positive number in radians
    printf("The sine of %lf is %lf \n", 2.3, sin(2.3));

    // negative number in radians
    printf("The sine of %lf is %lf \n", -2.3, sin(-2.3));

    //converting the degrees angle into radians and then applying sin()
    // degrees = 45.0
    // PI = 3.14159265
    // result first converts degrees to radians then apply sin
    double result=sin(45.0 * (3.14159265 / 180.0));
    printf("The sine of %lf is %lf \n", 45.0, result);


}