Answer: OPTION 3
Explanation:
First of all, you need to know the concept of imaginary number or i.
i (imaginary number)=√-1
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√-48=√16 × √3 × √-1 ⇔ This splitting is just help you to understand better.
√16=4 ⇔ This is a perfect square
√3=√3 ⇔ Nothing to change
√-1=i ⇔ imaginary number as mentioned before.
√-48=√16 × √3 × √-1
√-48=4 × √3 × i
√-48=4i√3