# C++ Math log1p()

The function computes the natural logarithm of a given number plus one.

## Parameter

x: The value of which logarithm is to be calculated.

## Return value

Parameter Return value
x>0 Positive
x=0 zero
0>x> -1 Negative
x= -1 -infinity
x<-1 Not a Number(nan)

## Example 1

Let's see a simple example when the value of x is greater than zero.

Output:

```Value of x is : 10
log1p(x) = 2.3979
```

In this example, log1p() function computes the logarithm value when x is greater than zero.

## Example 2

Let's see a simple example when the value of x is zero

Output:

```Value of x is : 0
log1p(x) = 0
```

In this example, log1p() function computes the logarithm value when the value of x is zero.

## Example 3

Let's see a simple example when the value of x is less than zero.

Output:

```Value of x is : -0.5
log1p(x) = -0.693147
```

In this example, log1p() function computes the logarithm value when the value of x is less than zero.

## Example 4

Let's see the simple example when the value of x is -1.

Output:

```Value of x is : -1
log1p(x) = -inf
```

In this example, log1p() function computes the logarithm value when the value of x is -1.

## Example 5

Let's see the simple example when the value of x is less than -1.

Output:

```Value of x is : -3
log1p(x) = -nan
```

In this example, log1p() function computes the logarithm value when the value of x is less than -1.

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