I need to show that \(\lim_{N\to\infty} \frac{(1-\frac{r}{N})^x\frac{r}{N}}{N}\)
Becomes \(re^{-rx}\)
Hint That was given:
Remember that \(\lim_{N\to\infty} (1+\frac{a}{N})^{bN} = e^{ab}\)