# Y = (-1)^x

1. May 31, 2013

### cp255

So I was thinking about the equation y=(-1)x. This equation will jump back and fourth across the x-axis depending on weather x is even or not. This must mean that the function is discontinuous. Figuring out if the value is positive or negative is straight forward for ration numbers but how can we tell if say (-1)^pi is negative or positive since we don't know if pi is even or odd.

2. May 31, 2013

### SteamKing

Staff Emeritus
It's not that simple. Remember x is a continuous variable, and the quality of even or odd applies only to integers. There are no even or odd rational or irrational numbers.

The equation in the OP is defined for real numbers only when abs(x) > 0. Do you know what y equals when x equals 1/2?

Last edited: May 31, 2013
3. May 31, 2013

### cp255

I never thought of what it would be be when x=0.5. So I guess it can be positive negative or undefined.

4. May 31, 2013

### SteamKing

Staff Emeritus
Don't you know what it means to raise a number to a power of 0.5? Does square root come to mind?

What is the square root of -1?