C++ Usage and examples of sqrt() function

C++ Library Function <cmath>

C ++The sqrt() function in it returns the square root of the number.

　√x = sqrt(x)

This function is in<cmath>defined in the header file.

The prototype of sqrt() [from C ++ 11[Standard library begins]

double sqrt(double x);
float sqrt(float x);
long double sqrt(long double x);
double sqrt(T x);　//is an integer type

The sqrt() parameter

The sqrt() function takes a single non-negative parameter.

An error will occur if a negative parameter is passed to the sqrt() function.

The return value of sqrt()

The sqrt() function returns the square root of the given parameter.

Example1How sqrt() works in C ++How does the work in Chinese?

#include <iostream>
#include <cmath>
using namespace std;
int main()
{
	double x =　10.25, result;
	result = sqrt(x);
	cout << "10.25The square root is " << result << endl;
	return 0;
}

The output when running the program is:

10.25The square root is　3.20156

Example2：sqrt() function with integer parameter

#include <iostream>
#include <cmath>
using namespace std;
int main()
{
	long x =　464453422;
	double result = sqrt(x);
	cout << "464453422The square root is " << result << endl;
	return 0;
}

The output when running the program is:

464453422The square root is　21551.2

　C++ Library Function <cmath>