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Header filemath.h
Declarationfloat logf(float num);
double log(double num);
long double logl(long double num);
Returnreturns the natural logarithm for num.


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

  int main(void)
  {
    double val = 1.0;

    do {
      printf("%f %f\n", val, log(val));
      val++;
    } while (val<11.0);

    return 0;
  }

1.000000 0.000000
2.000000 0.693147
3.000000 1.098612
4.000000 1.386294
5.000000 1.609438
6.000000 1.791759
7.000000 1.945910
8.000000 2.079442
9.000000 2.197225
10.000000 2.302585








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