# Math Help - Why doesn't this function work when x<0 ?

1. ## Why doesn't this function work when x<0 ?

f(x)=x^pi

Thanks

2. Originally Posted by goc335
f(x)=x^pi

Thanks
For arbitrary $b\in\mathbb{R}$, $x^b$ is defined to be nothing other than the value of $\mathrm{e}^{b\cdot\ln(x)}$. If you can define $\ln(x)$ for negative x, fine (I would be surprised if you could, but then: who am I?), if you can't: there you go!