Algebra Examples

$f (- 1) = \sqrt{- 1 - 3}$

Step 1

Subtract $3$ from $- 1$ .

$f (- 1) = \sqrt{- 4}$

Step 2

Rewrite $- 4$ as $- 1 (4)$ .

$f (- 1) = \sqrt{- 1 \cdot 4}$

Step 3

Rewrite $\sqrt{- 1 (4)}$ as $\sqrt{- 1} \cdot \sqrt{4}$ .

$f (- 1) = \sqrt{- 1} \cdot \sqrt{4}$

Step 4

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

$f (- 1) = i \cdot \sqrt{4}$

Step 5

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

$f (- 1) = i \cdot \sqrt{2^{2}}$

Step 6

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

$f (- 1) = i \cdot 2$

Step 7

Move $2$ to the left of $i$ .

$f (- 1) = 2 i$