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6 solutions
Very easy!
1) 1 6 + 9 = 4 + 3 = 7 (No)
2) 3 − 2 1 × 2 = 3 − 1 = 2 (No)
3) sin 4 5 = 2 1 (No)
4) 6 + i 2 = 6 − 1 = 5 ( i 2 = − 1 ) (Yes)
Thus, 6 + i 2 = 5 is the answer.
how can a square no. be negative
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in complex numbers the root of -1 is equal to ' i ', ' i ' is an imaginary number it actually does not exist as i is root of -1 its square will be equal to -1
There is no real solution. So... Lets IMAGINE the answer
thnx
Brilliant isn't all about streaks and ratings; it's about exploring different types of problems to learn more, not to earn points to look good while you don't actually learn anything! (I don't mean you can't learnt anything from this problem)
Anyway, since i 2 = − 1 , 6 + i 2 = 6 + ( − 1 ) = 6 − 1 = 5 , and we are done.
I would like to request the Brilliant.org staff to allow us to view the other options of the question after we have solved it. Now, when I'm trying to explain why the other options are wrong, I can't find it :)
how can a square number be negative?
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Because i is an imaginary number,it means "the square root of negative one".
Exactly. They should allow us to view the other options
we know i^2=-1 then 6-1=5
i^2 = -1, 6 + i^2 = 5
6 + i 2 = 6 + ( − 1 ) = 5