| InvalidOperationException | x is signaling NaN | 
| UnderflowException | 2x - 1 is too small to be represented | 
| OverflowException | 2x - 1 is too big to be represented | 
| InexactException | the result is inexact | 
| x | exp2m1(x) | 
|---|---|
| NaN | NaN | 
| ±0.0 | ±0.0 | 
| -∞ | -1.0 | 
| +∞ | +∞ | 
decimal32 x = 3; assert(exp2m1(x) == 7);
Calculates 2x - 1