Is a + b <= 1?
1) a ^ 2 + b ^ 2 <= 1
2) a ^ 2-b ^ 2 <= 1
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a + b <= 1
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colakumarfanta
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nicktimoshenko
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Еcolakumarfanta wrote:Is a + b <= 1?
1) a ^ 2 + b ^ 2 <= 1
2) a ^ 2-b ^ 2 <= 1
statement B: 0,51*0,51*0,51*0,51 <=1
A: 0.51*0.51*2<=1
but 0.51*2 >1
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arohan_sambyal
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Statement i
a=0.6=b, satisfies choice A and a+b>=1
a=-0.6=b, satisfies choice A and a+b<=1
Therefore statement 1 Is not sufficient
Statement ii
a^2-b^2=(a+b)(a-b)<=1 ,
a=0.6 and b =0.7 , a^2-b^2<=1 and a+b>=1
a=0.5 and b=0.1, a^2-b^2<=1 and a+b<=1
therefore statement 2 is not sufficient
ANSWER : CHOICE E
a=0.6=b, satisfies choice A and a+b>=1
a=-0.6=b, satisfies choice A and a+b<=1
Therefore statement 1 Is not sufficient
Statement ii
a^2-b^2=(a+b)(a-b)<=1 ,
a=0.6 and b =0.7 , a^2-b^2<=1 and a+b>=1
a=0.5 and b=0.1, a^2-b^2<=1 and a+b<=1
therefore statement 2 is not sufficient
ANSWER : CHOICE E
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nicktimoshenko
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agreearohan_sambyal wrote:Statement i
a=0.6=b, satisfies choice A and a+b>=1
a=-0.6=b, satisfies choice A and a+b<=1
Therefore statement 1 Is not sufficient
Statement ii
a^2-b^2=(a+b)(a-b)<=1 , can happen only if (a+b)<=1
So statement 2 is sufficeint
ANSWER : CHOICE B
I mistook "-"for "*"
