Question

PLZ help me fast 2 mins left

Answer 1

Answer:

$\sqrt{-5}=i\sqrt{5}$

$\sqrt{-25}=5i$

Step-by-step explanation:

i is an imaginary unit, this means

$i^2=-1$

Rewrite -5 as $5\cdot (-1)=5\cdot i^2,$

then

$\sqrt{-5}=\sqrt{5i^2}=\sqrt{5}\cdot \sqrt{i^2}=\sqrt{5}\cdot i=i\sqrt{5}$

Rewrite -25 as $-25=25\cdot (-1)=25\cdot i^2,$

then

$\sqrt{-25}=\sqrt{25\cdot i^2}=\sqrt{25}\cdot \sqrt{i^2}=5\cdot i=5i$