# sqrt(), sqrtl() and sqrtf() in C++

## Library FunctAion in C++ – sqrt(), sqrtl() and sqrtf()

There are several ways to calculate the square root of a number in C++. The most common way is to use the sqrt() function from the cmath library, which is a part of the C++ standard library.  The cmath header file contains two other inbuilt functions sqrtl() and sqrtf() for calculating the square root of a number having arguments of type long double and float respectively. ## C++ Library Function cmath sqrt()

In C++, the `sqrt()` function is included in `cmath` header file.

The `sqrt()` function is used to compute the square root of a number. Square root of a number is a value, which on multiplication by itself, gives the original number.

### Syntax

```double sqrt(double x);
```

`sqrt()` function return a double data type as result or as a square root of a number.,

### Example:

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

int main() {

double x = 9.0;
double y = sqrt(x);

cout << "The square root of " << x << " is " << y << endl;

return 0;
}

```

### Output

```The square root of 9 is 3
```

## C++ Library Function cmath sqrtl()

In C++, the `sqrtl()` function is included in `cmath` header file.

The `sqrtl()` function is used to compute the square root of a long double value. This function has output with more precision.

### Syntax

```long double sqrtl(long double x);
```
`sqrtl()` function returns a long double data type as result or as a square root of a number.

### Example:

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

int main() {

long double x = 1345.0;
long double y = sqrtl(x);

cout << "The square root of " << x << " is " << y << endl;

return 0;
}
```

### Output

```The square root of 1345 is 36.6742
```

## C++ Library Function cmath sqrtf()

In C++, the `sqrtf()` function is included in `cmath` header file.

The `sqrtf()` function is used to compute the square root of a float value.

### Syntax

```float sqrtf(float x);
```
`sqrtf()` function returns a float data type as result or as a square root of a number.

### Example:

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

int main() {

float x = 15.67;
float y = sqrtf(x);

cout << "The square root of " << x << " is " << y << endl;

return 0;
}

```

### Output

```The square root of 15.67 is 3.95854
```

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