if x is not equal to y, is xy = 1?
1) x +1 / y = y +1 / x
2) (x + y) ^ 2 = x ^ 2 + y ^ 22
Inequality
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would go with D
1) x +1 / y = y +1 / x
=>xy=1/x  1/y
=>xy=(yx)/xy
=>xy= (xy)/xy
=>xy=1
hence statement 1 is sufficient as well
1) x +1 / y = y +1 / x
=>xy=1/x  1/y
=>xy=(yx)/xy
=>xy= (xy)/xy
=>xy=1
hence statement 1 is sufficient as well

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each statement individually sufficient to answer
option D
2nd statement > (x+y)^2=x^2+y^22
2XY+2=0 => XY=1
1st statement
x+1/y=y+1/x
=> (xy+1)(1/y1/x)=0 so either xy=1 or from the second piece x=y which is not the case as mentioned in the question .
So solution is xy=1
option D
2nd statement > (x+y)^2=x^2+y^22
2XY+2=0 => XY=1
1st statement
x+1/y=y+1/x
=> (xy+1)(1/y1/x)=0 so either xy=1 or from the second piece x=y which is not the case as mentioned in the question .
So solution is xy=1