Question

simplify √-63
7i√9
7i√3
9i√7
3i√7

Explanation:

Step1: Rewrite -63 as product

$\sqrt{-63}=\sqrt{-1\times63}$

Step2: Use square - root property

Since $\sqrt{ab}=\sqrt{a}\cdot\sqrt{b}$ ($a = - 1$, $b = 63$) and $\sqrt{-1}=i$, we have $\sqrt{-1\times63}=\sqrt{-1}\cdot\sqrt{63}=i\sqrt{63}$

Step3: Simplify $\sqrt{63}$

$\sqrt{63}=\sqrt{9\times7}=\sqrt{9}\cdot\sqrt{7}=3\sqrt{7}$

Step4: Combine results

$i\sqrt{63}=3i\sqrt{7}$

Answer:

$3i\sqrt{7}$