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gcc - C Build error when getting the value of sin()

I have recently started learning C as a side project. I am working under OpenSuse with the latest NetBeans using the GCC as toolset for compiling. One of the very first programs that I made was this:

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

/*
 * 
 */
int main(int argc, char** argv) {    
    double rad = 1;
    double result = 0;
    result = sin(rad);
    return (EXIT_SUCCESS);
}

This is a simple, no-brainer example that should have worked without a problem. However, I get a Build Error: Exit code 2(error in line 18, undefined reference to sin) when trying to compile. Interestingly enough, if I remove the assignment of the value of sin(rad) to result OR replace rad with a hard coded value, the program compiles just fine. What am I doing wrong here?

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by (71.8m points)

In C, you need to link to the math library:

Add this to the command line options:

-lm

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