Evaluate 2 square root of -16

$2 \sqrt{- 16}$

Step 1

Rewrite $- 16$ as $- 1 (16)$ .

$2 \sqrt{- 1 (16)}$

Step 2

Rewrite $\sqrt{- 1 (16)}$ as $\sqrt{- 1} \cdot \sqrt{16}$ .

$2 (\sqrt{- 1} \cdot \sqrt{16})$

Step 3

Rewrite $\sqrt{- 1}$ as $i$ .

$2 (i \cdot \sqrt{16})$

Step 4

Rewrite $16$ as $4^{2}$ .

$2 (i \cdot \sqrt{4^{2}})$

Step 5

Pull terms out from under the radical, assuming positive real numbers.

$2 (i \cdot 4)$

Step 6

Move $4$ to the left of $i$ .

$2 (4 \cdot i)$

Step 7

Multiply $4$ by $2$ .

$8 i$