Hey y'all, as the title says, I'm a wee bit stuck trying to use the math.h library function "pow". Here's my code -

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

int main(int argc, char *argv[]) {

//OMITTED CODE

size_t i;
double j;
int k;
for(i = argLen - 1, k = 0; k < argLen; i--, k++) {
	j = pow(16, i);
	deciVals[k] = deciVals[k] * j;
}

//OMITTED CODE	

return 0;

}

Despite having math.h included, and using the -lm option for the GCC, I'm still getting this error -

>gcc -lm -o output hexConverter.c
/usr/bin/ld: /tmp/ccghjuxO.o: in function `main':
hexConverter.c:(.text+0x237): undefined reference to `pow'
collect2: error: ld returned 1 exit status

Any help would be appreciated, thanks guys.

I'm trying to do my homework which is to make a program that calculates a hypotenuse, given two cathetus entered by the user. This is the code:

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

int main(void) {

    float primeiroCateto;
    float segundoCateto;
    float hipotenusa;

    setlocale(LC_ALL, "Portuguese");

    printf("Digite o valor do primeiro cateto:\n");
    scanf("%f", &primeiroCateto);
    printf("Digite o valor do segundo cateto:\n");
    scanf("%f", &segundoCateto);

    hipotenusa = sqrt(pow(primeiroCateto, 2) + pow(segundoCateto, 2));

    printf("A hipotenusa é igual a:\n%.2f", hipotenusa);
    return 0;
}

The problem is that when i try to copile the code using:

gcc -Wall -Wextra -o Atividade2_exercício5 Atividade2_exercício5.c

This error shows up:

/tmp/ccFsAgvS.o: In function `main':
Atividade2_exercício5.c:(.text+0x82): undefined reference to `pow'
Atividade2_exercício5.c:(.text+0x9d): undefined reference to `pow' 
Atividade2_exercício5.c:(.text+0xa7): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status

So what to do now? (i'm using vccode by the way)