# C++ Program - Cube Root of a Number

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

x3 = y

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

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

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

int main() {
double x = 64;
double y = 125;

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

The above code will give the following output:

```Cube root of 16.0 is 4.0
Cube 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 cube root of a number.

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

int main() {
double x = 64;
double y = 125;

double x1 = pow(x, 1/3.0);
double y1 = pow(y, 1/3.0);
cout<<"Cube root of "<<x<<" is "<<x1<<"\n";
cout<<"Cube root of "<<y<<" is "<<y1<<"\n";
return 0;
}
```

The above code will give the following output:

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

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