Question

express 9.2 - 3√-8 as a complex number in the form of a + bi. what is the imaginary term?

Explanation:

Step1: Simplify the square - root of negative number

Recall that $\sqrt{-8}=\sqrt{8}\times\sqrt{-1}$. Since $\sqrt{-1}=i$ and $\sqrt{8} = 2\sqrt{2}$, then $\sqrt{-8}=2\sqrt{2}i$.

Step2: Write the complex - number form

The expression $9.2-3\sqrt{-8}$ can be rewritten as $9.2-3\times2\sqrt{2}i=9.2 - 6\sqrt{2}i$. The imaginary term is $- 6\sqrt{2}i$.

Answer:

$-6\sqrt{2}i$