Answer: OPTION B
Explanation:
First of all, you need to know the concept of imaginary number or i.
i (imaginary number)= √-1 ⇔ In real number world, √-1 will be undefined,
and thus this is called imaginary number
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√-2=√2 × √-1
√-2=√2× √-1
√-2=√2 × i
√-2= √2 i
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√-18=√9 × √2 × √-1
- √9=3 ⇒ This is a perfect square
- √2=√2
- √-1=i
√-18= √9 × √2 × √-1
√-18= 3 × √2 × i
√-18= 3√2 i
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Addition in radical numbers is as usual as normal number. HOWEVER, only numbers that has the same radical (i.e 2√3 and 7√3) can combine.
√-2 + √-18
=√2 i + 3√2 i
=4√2 i
Hope this helps!! :)
Please let me know if you have any question