Question

Simplify the number using the imaginary unit i:

(square root) -28

options:
a. 2(square root) -7
b. -2(square root) -7
c. i(square root) 28
d. 2i(square root) 28

Answer 1

Ok so it is \[\large{\sqrt{-28}}\]

Correct?

Answer 2

Factor 28 first to find the perfect square.
and remember that i=√(-1)

Answer 3

Yes. @SheldonEinstein

Answer 4

\[\large{\sqrt{-28} = \sqrt{-1}\sqrt{28} = \sqrt{-1} \sqrt{4*7}}\]

Answer 5

So it will be \[\large{(\sqrt{-1}) 2\sqrt{7} }\]

Answer 6

Now as we know that \[\large{\sqrt{-1} = i (\textbf{IOTA})}\]

Answer 7

So we have answer : \(\large{ i \sqrt{28} }\)

Answer 8

Got it?

Answer 9

Yes thanks for both of your help and Sheldon for explaining so well :)

Answer 10

You're welcome and thanks for the appreciation.

Answer 11

i√28 is not fully simplified.

Answer 12

Options have isqrt{28}

Answer 13

Hence no need to simplify further.

Answer 14

Ah, yes. After a second look 2i√7 isn't an option.

Answer 15

Yeah, at first I thought the same and hence simplified it further but when saw the options again , I got to see the option i sqrt{28}...