# C++ <complex> - exp() Function

The C++ <complex> exp() function returns base-e exponential of a complex number z, that is e (Euler's number, 2.7182818) raised to the power of z, ez. It is a function on complex plane, and has no branch cuts.

Mathematically, it can be expressed as: where, z = x+iy

### Syntax

```template<class T>
complex<T> exp (const complex<T>& z);
```

### Parameters

 `z` Specify the complex number.

### Return Value

Returns e raised to the power of z.

### Example:

The example below shows the usage of exp() function.

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

int main (){
complex<double> z1 (2, 2);
complex<double> z2 (2, 0);
complex<double> z3 (0, 2);

//calculate the exponential of given value
cout<<"exp(z1): "<<exp(z1)<<"\n";
cout<<"exp(z2): "<<exp(z2)<<"\n";
cout<<"exp(z3): "<<exp(z3)<<"\n";

return 0;
}
```

The output of the above code will be:

```exp(z1): (-3.07493,6.71885)
exp(z2): (7.38906,0)
exp(z3): (-0.416147,0.909297)
```

❮ C++ <complex> Library

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