5. Find the radius of convergence and interval of convergence of the series \( \sum_{n=0}^{\infty} \frac{(-3)^n x^n}{\sqrt{n+1}} \). (15%)
5. Find the radius of convergence and interval of convergence of the series \( \sum_{n=0}^{\infty} \frac{(-3)^n x^n}{\sqrt{n+1}} \). (15%)