Write in terms of i.
-$\sqrt { - 168 }$
A) $2 \mathrm { i } \sqrt { 42 }$
B) $- 2 \sqrt { 42 }$
C) $- 2 \mathrm { i } \sqrt { 42 }$
D) $2 \sqrt { 42 }$

Question

Quizplus · Accepted Answer

The square root of a negative number can be expressed in terms of i, where i is the imaginary unit defined as $\sqrt{-1}$. Thus, $\sqrt{-168} = \sqrt{168} \cdot \sqrt{-1} = \sqrt{4 \cdot 42} \cdot i = 2\sqrt{42} \cdot i$, which matches choice A.

Write in Terms of I −168\sqrt { - 168 }−168​ A) 2i422 \mathrm { i } \sqrt { 42 }2i42​

Write in Terms of I $\sqrt { - 168 }$ A) $2 \mathrm { i } \sqrt { 42 }$