Complex Number E0136E

1. The problem is to understand and simplify the expression $-\frac{i\sqrt{15}}{3}$. 2. This expression is a complex number in the form $a + bi$, where $a=0$ and $b=-\frac{\sqrt{15}}{3}$. 3. The imaginary unit $i$ satisfies $i^2 = -1$. 4. The expression cannot be simplified further because $\sqrt{15}$ is already in simplest radical form and the fraction is reduced. 5. Therefore, the expression $-\frac{i\sqrt{15}}{3}$ represents a purely imaginary number with magnitude $\frac{\sqrt{15}}{3}$ and negative imaginary part. Final answer: $-\frac{i\sqrt{15}}{3}$