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Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 01:15
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Competition Mode Question Is \(x^3 − 1 = 0\) ? (1) \(x^2 = 1\) (2) \(x^2 = x\)
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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 01:32
Is \(x^3 − 1 = 0\)? (1) \(x^2 = 1\) \(x^2  1 = 0\) x = 1 YES or x =  1 NO INSUFFICIENT (2) \(x^2 = x\) \(x^2  x = 0\) \(x(x  1) = 0\) x = 0 NO OR x = 1 YES INSUFFICIENT Together 1 and 2 x = 1 YES SUFFICIENT. Answer C.
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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 01:40
Is x^3  1 = 0?
Statement 1: x^2=1 This means x=1 or x=1 Insufficient because when x=1 x^3  1 = 0 but when x=1, x^3  1 = 2
Statement 2: x^2=x This mean x=0 or x=1 Insufficient. When x=0, x^3  1 = 1, but when x=1, x^3  1 = 0.
1+2 Sufficient since we know that x=1 is common to both statements, hence x=1 and x^3  1 =0
The answer is C.



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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 01:57
Question: Is \(x^3 − 1=0\) ?
(1) \(x^2 = 1\) > \(x = 1\) or \(1\) > \(x^3 = 1\) or \(1\) > Insufficient
(2) \(x^2 = x\) > \(x^2  x = 0\) > \(x(x  1) = 0\) > \(x = 0\) or \(1\) > \(x^3 = 0\) or \(1\) > Insufficient
Combining (1) & (2), > \(x = 1\) ONLY > Sufficient
Option C



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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 02:19
(1) x^2 = 1 > x=1 or x=1 If x=1, then x^3 − 1 = 2 (no) If x=1, then x^3 − 1 = 0 (yes) NOT SUFFICIENT
(2) x^2 = x > x=0 or x=1 If x=0, then x^3 − 1 = 1 (no) If x=1, then x^3 − 1 = 0 (yes) NOT SUFFICIENT
(1)+(2) turns out we havwe only single solution: x=1, then x^3 − 1 = 0 (yes) SUFFICIENT
FINAL ANSWER IS (C)
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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 03:00
#1 x^2=1 x= +/1 insufficient #2 x^2x=0 x= 0 or x= 1 insufficient from 1&2 x= 1 IMO C
Is x3−1=0 ?
(1) x2=1
(2) x2=x



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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 08:04
For x^31=0 X can only be 1
1) from this X can be 1,1..... INSUFFICIENT 2) from this X can be 0,1.... INSUFFICIENT
Combining both we can get X=1
OA:C
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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 08:25
Quote: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x Question: Is x^3 = 1?Statemnt 1: x^2 = 1i.e. x = +1 i.e. x^3 = +1 NOT SUFFICIENT Statement 2: x^2 = xi.e. x = 0 or 1 i.e. x^3 = 0 or 1 NOT SUFFICIENT COmbining the two statementsx^3 = 1 SUFFICIENT Answer: Option C
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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 11:31
Is x^3  1 = 0?
In other words, we are trying to find out if x^3 is equal to 1
(1) "x^2 = 1" x could be equal to 1, which would make the equation correct. However, x could also equal 1, which would make the equation incorrect. INSUFFICIENT.
(2) "x^2 = x" x could equal 1, which would make the equation correct. However, x could also equal 0, which would make the equation incorrect. INSUFFICIENT.
(1+2) The only value of x that satisfies both statements is 1, so we can definitively say the equation is correct. SUFFICIENT.
Answer: (C)



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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 11:41
Quote: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x (1) insufic x^21=0, (x1)(x+1)=0, x={1,1} (2) insufic x^2=x, x^2x=0, x(x1)=0, x={0,1} (1/2) sufic x=1 Ans (C)



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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 20:37
Is\( x^3−1=0 \)? (1) \(x^2=1\) (2) \(x^2=x\) Is\( x^3−1=0 \)? or x = 1 (1) \(x^2=1\) x can be 1 or 1 (Not sufficient) (2) \(x^2=x\) or \(x^2x =0\) or \(x(x1)=0\) thus x = 0 ,1 Not sufficient Combine both only value common is 1 thus \(x^3−1=0 \) , sufficient Thus C
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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 21:35
Is \(x^{3} —1 =0 \)??? —>\( x^{3} =1\) —> \(x= 1\) ???
(Statement1): \(x^2 = 1\) —>\(( x—1)(x+1)= 0\) \(x= 1\) and \(x= —1\) Insufficient
(Statement2): \(x^{2} = x\) —>\( x( x—1) = 0\) \(x = 0\) and \(x= 1\) Insufficient
Taken together 1&2, Only \(x= 1\) satisfies the both statements Sufficient
Answer (C)
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Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 21:53
Is \(x^3 − 1 = 0\) ?
we need to find if X^31=0 or X^3=1
(1) \(x^2 = 1\)
X^2=1 means X=1 this means X^31 =0 Hence statement 1 is sufficient.
(2) \(x^2 = x\)
X^2=X Therefore X^2X=0, X(X1)=0 means X=0 or X=1
if X=0 the X^31= 1 If X=1 the X=0 hence insufficient
statement 1 is sufficient IMO A




Re: Is x^3 − 1 = 0 ? (1) x^2 = 1 (2) x^2 = x
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31 Mar 2020, 21:53




