Question

How to use log() function to calculate the natural base e logarithm in C++

Answer 1

#include <iostream>
#include <cmath>

using namespace std;

int main()
{
	cout << "log(1) = " << log(1) << endl;
	cout << "log(5) = " << log(5) << endl;
	cout << "log(100) = " << log(100) << endl;
	cout << "log(125) = " << log(125) << endl;
	cout << "log(125) / log(5) = " << log(125) / log(5) << endl;
	cout << "log(3.5) = " << log(3.5) << endl;

	return 0;
}

/*
run:

log(1) = 0
log(5) = 1.60944
log(100) = 4.60517
log(125) = 4.82831
log(125) / log(5) = 3
log(3.5) = 1.25276

*/

 

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