Question

Simplify using i

Answer 1

First what you would do is simplify it down. Since both are negative you would take out an i from both, making it i\[\sqrt{15} i \sqrt{4}\]
Since there is a square root for 4, which is 2 it would change to i\[\sqrt{15}\] (2i)

so thye final answer would be 2i^2(rad15)

Answer 2

\[ \sqrt{-15} = i\sqrt{15} \]
\[ \sqrt{-4} = i \sqrt{4} =2i \]
so \[\sqrt{-15}\sqrt{-4} = 2i\cdot i \sqrt{15} = -2\sqrt{15} \]