Which function is used to calculate the arctangent of a number in C?

The function used to calculate the arctangent of a number in C is atan(). Here is how you can use it:

1. First, you need to include the math library at the beginning of your program. You can do this by adding #include <math.h> at the top of your code.

2. Once you've included the math library, you can use the atan() function to calculate the arctangent of a number. The function takes a single argument, which is the number you want to calculate the arctangent of.

Here is an example of how to use the atan() function:

#include <math.h>
#include <stdio.h>

int main() {
    double num = 1.0;
    double result;

    result = atan(num);

    printf("The arctangent of %lf is %lf degrees", num, result);

    return 0;
}

In this example, the atan() function calculates the arctangent of 1.0, and the result is stored in the result variable. The printf() function then prints the result.

The function used to calculate the arctangent of a number in C is atan(). Here is how you can use it:

1. First, you need to include the math library at the top of your C program. This is done by adding #include <math.h>.

2. Then, you can use the atan() function to calculate the arctangent of a number. The function takes a single argument, which is the number you want to calculate the arctangent of.

Here is an example:

#include <math.h>
#include <stdio.h>

int main() {
    double num = 1.0;
    double result;

    result = atan(num);

    printf("The arctangent of %lf is %lf degrees", num, result);

    return 0;
}

In this example, atan(num) will return the arctangent of num in radians. If you want to convert it to degrees, you can multiply the result by 180/PI.