# C++ Program - Square Root of a Number

If a number is multiplied by itself (n*n), the final number will be the square of that number and finding the square root of a number is inverse operation of squaring the number. If x is the square root of y, it can be expressed as below: Alternatively, it can also be expressed as:

x2 = y

### Method 1: Using sqrt() function of C++ <cmath> header file

The sqrt() function of C++ <cmath> header file can be used to return square root of a number.

```#include <iostream>
#include <cmath>
using namespace std;

int main() {
double x = 16;
double y = 25;

double x1 = sqrt(x);
double y1 = sqrt(y);
cout<<"Square root of "<<x<<" is "<<x1<<"\n";
cout<<"Square root of "<<y<<" is "<<y1<<"\n";
return 0;
}
```

The above code will give the following output:

```Square root of 16.0 is 4.0
Square root of 25.0 is 5.0
```

### Method 2: Using pow() function of C++ <cmath> header file

The pow() function of C++ <cmath> header file can also be used to calculate square root of a number.

```#include <iostream>
#include <cmath>
using namespace std;

int main() {
double x = 16;
double y = 25;

double x1 = pow(x, 0.5);
double y1 = pow(y, 0.5);
cout<<"Square root of "<<x<<" is "<<x1<<"\n";
cout<<"Square root of "<<y<<" is "<<y1<<"\n";
return 0;
}
```

The above code will give the following output:

```Square root of 16.0 is 4.0
Square root of 25.0 is 5.0
```

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