Question

Simplify. 3√-28 A 2i√7 B 12i√7 C 61√7 D -6i√7

Answer 1

Answer:

C

Step-by-step explanation:

We want to simplify the expression:

$\displaystyle 3 \sqrt{-28}$

Rewrite:

$\displaystyle = 3 \sqrt{ 4\cdot 7 \cdot -1}$

Rewrite:

$\displaystyle = 3 \cdot \sqrt{4} \cdot \sqrt{7} \cdot \sqrt{-1}$

Simplify. Let i = √(-1). Hence:

$\displaystyle = 3 \cdot \left(2\right) \cdot \left(i\right) \cdot \sqrt{7}$

Multiply:

$\displaystyle = 6i\sqrt{7}$

In conclusion, our answer is C.