Compute the natural logarithm of 2, by adding up to n terms in the series
1 - 1/2 + 1/3 - 1/4 + 1/5 -... 1/n
where n is a positive integer and input by user.
Source Code
#include<iostream>
using namespace std;
int main()
{
int i,n,sign=-1;
float sum=0;
cout<<"Enter the value of n ";
cin>>n;
for(i=1;i<=n;i++)
{
sign *= -1;
sum += sign*1.0/i;
}
cout<<"log 2 : "<<sum;
return 0;
}
Output
SAMPLE RUN # 1 Enter the value of n 5 log 2 : 0.783333 SAMPLE RUN # 2 Enter the value of n 10000 log 2 : 0.693091