Question

What is the sum of StartRoot negative 2 EndRoot and StartRoot negative 18 EndRoot?

Answer 1

Answer:

$4 \sqrt{2} i$

Step-by-step explanation:

We want to find the sum of

$\sqrt{ - 2} + \sqrt{ - 18}$

We can rewrite this as

$\sqrt{ 2 \times - 1} + \sqrt{ 18 \times - 1}$

This becomes;

$\sqrt{2} \times \sqrt{ - 1} + \sqrt{18} \times \sqrt{ - 1}$

Recall that;

$i = \sqrt{ - 1}$

This implies that;

$\sqrt{2} i + 3 \sqrt{2} i$

Combine like terms:

$4 \sqrt{2} i$