一道作业题： 指数函数出错请教 pow(num, 0.25)
#include <stdio.h>
#include <math.h>
int main()
{
float num, result;

printf( "Enter a number here: ");
scanf( "%f ", &num);
result = pow(num, 0.25);
printf( "%f raised to the 1/4 thd power is %f\n ", num, result);

return 0;
}

编译时提示
$ gcc -o 3_6_5 3_6_5.c
/tmp/ccIOqWWD.o: In function `main ':
3_6_5.c:(.text+0x47): undefined reference to `pow '
collect2: ld 返回 1


请教一下时怎么回事

[解决办法]
改成这样

result = pow(num, 0.25f);


[解决办法]
result = (float)pow((double)num, 0.25);
[解决办法]
#include <stdio.h>
#include <math.h>
int main()
{
float num, result;-----double num,result;

printf( "Enter a number here: ");
scanf( "%f ", &num);----------------- "%f "---> "%lf "
result = pow(num, 0.25);
printf( "%f raised to the 1/4 thd power is %f\n ", num, result);

return 0;
}