if x is not equal to y, is xy =- 1?
1) x +1 / y = y +1 / x
2) (x + y) ^ 2 = x ^ 2 + y ^ 2-2
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Inequality
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colakumarfanta
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scoobydooby
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would go with D
1) x +1 / y = y +1 / x
=>x-y=1/x - 1/y
=>x-y=(y-x)/xy
=>x-y= -(x-y)/xy
=>xy=-1
hence statement 1 is sufficient as well
1) x +1 / y = y +1 / x
=>x-y=1/x - 1/y
=>x-y=(y-x)/xy
=>x-y= -(x-y)/xy
=>xy=-1
hence statement 1 is sufficient as well
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debmalya_dutta
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each statement individually sufficient to answer
option D
2nd statement -> (x+y)^2=x^2+y^2-2
2XY+2=0 => XY=-1
1st statement
x+1/y=y+1/x
=> (xy+1)(1/y-1/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^2-2
2XY+2=0 => XY=-1
1st statement
x+1/y=y+1/x
=> (xy+1)(1/y-1/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
