vasili wrote:
If y is not equal to 1, is x = 1?
(1) x^2 + y^2 = 1
(2) y = 1 - x
Hi
I am not sure if this is correct solution, someone kindly help
If y is not equal to 1, is x = 1?
1) x^2 + y^2 = 1
2) y = 1 - x
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Statement1
x^2 + y^2 = 1
y=0 , x=1 --> x=1 Yes
but y and x need not be integers so y = x = sqrt(0.5) --> x=1 No
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Statement2
y = 1 - x
x=1, Y=0 --> x=1 Yes
x=0.5 , Y = 0.5 --> x=1 No
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1+2
Here I checked all ranges
Case1
If x=0 then Y=1 which can not be true
So x=1 and Y=0
x=1 Yes
Case2
x between 0 and 1
x=0.1 y=0.9
x=0.5 y=0.5
x=0.9 y=0.1
As we know number between 0 and 1 , then x2<x so in this case x^2 + y^2 <> 1
so we cant consider this range
Case3
x between 0 and -1
this will be same as case2 , because square will be same for + and -ve
Case4
x >=1 here again x^2 + y^2 <> 1
so we cant consider this range
x<=-1 here again x^2 + y^2 <> 1
so we cant consider this range
Hence only x=1 and Y=0 works
IMO C
Someone please confirm if it is correct.