Please explain how do we solve this question. Also are there any number properties that helps solve this question quicker?
Note: Edited: Answer is (C) i.e. II. I had 2 windows open so mistook C to B (though I identified II as the answer).
1/sqrt(x+y)) is same as sqrt(x+y)/(x+y)
from properties, we know that if x,y > 0 then sqrt(x+y) < sqrt(x)+sqrt(y) (try plugging - rt(16)+rt(9) = 7 is more than rt(16+9) = 5)
then, II is definitely 'in' => answer can be C, E (A is ruled out because II is B is possible)
Now beginning elimination, E is ruled out as we are subtracting therefore reducing the numerator, and if Y is > X this would become -ve and we cannot say with certainty.
The answer can only be (B) i.e. II.
(Though the one angle that worries me a bit of the sign of the resultant operations...)
What is the OA?
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