TBT
If x and y are positive integers, is x even?
(1) \(x^y + y^x \)is even.
(2) \(y^x\)+ 4x is odd.
Pretty straightforward ques!
Question: Is x even ?
Statement 1(1) \(x^y + y^x \)is even.
As the sum of two terms is even, each term can be even or each term can be odd.
Hence, x and y both can be even or both x and y can be odd.
As we have two contradicting answers, we can eliminate A and D.
Statement 2(2) \(y^x\)+ 4x is odd.
\(y^x\) = odd - even
So \(y^x\) = odd.
As x is a positive integer, we can conclude that y is odd.
However, we don't have any information on x.
Hence the statement is not sufficient and we can eliminate B.
CombinedFrom Statement 1, we concluded that x and y follow the same even-odd nature.
From Statement 2, we know that y is odd.
Hence, we can conclude that x is odd.
The statements combined help answer the question.
Option C