Questions: Simplify.
-√(-40)
(A) -i √10
(B) i √10
(C) -2 i √10
(D) 2 i √10
Transcript text: Simplify.
\[
-\sqrt{-40}
\]
(A) $-i \sqrt{10}$
(B) $i \sqrt{10}$
(C) $-2 i \sqrt{10}$
(D) $2 i \sqrt{10}$
Solution
Solution Steps
Step 1: Rewrite the expression
The expression is \(-\sqrt{-40}\). Since the square root of a negative number involves the imaginary unit \(i\), we rewrite \(\sqrt{-40}\) as \(i\sqrt{40}\).
Step 2: Simplify the square root
Simplify \(\sqrt{40}\) by factoring it into \(\sqrt{4 \cdot 10}\). This becomes \(2\sqrt{10}\).
Step 3: Combine the terms
Substitute the simplified square root back into the expression: \(-i \cdot 2\sqrt{10}\). This simplifies to \(-2i\sqrt{10}\).
Step 4: Match with the given options
The simplified expression \(-2i\sqrt{10}\) matches option (C).