pls help. thank you. Very confuse with absolute problem.. Pls help.
Is |x| < 1?
1) |x+1| = 2|x-1|
2) |x-3 | not equal to 0
OA = C
Absolute problem
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Thepu,
If u go with stmt-1,
if x <1> 1, x = 3 -> Alone not SUFF
if u go with stmt-2,
x /= 3 -> Alone not SUFF.
Even if u go for both collectively, u can not reach to any conclusion.
IMO E. What's the OA? Guys am I missing something?
If u go with stmt-1,
if x <1> 1, x = 3 -> Alone not SUFF
if u go with stmt-2,
x /= 3 -> Alone not SUFF.
Even if u go for both collectively, u can not reach to any conclusion.
IMO E. What's the OA? Guys am I missing something?
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava
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see..
stmt 1 :: | x + 1 | = 2 | x - 1 |
if x>1 :: x+1 = 2x - 2 => x =3.
if -1 < x <1> x = 1/3.
if x<1> x = 3. This solution isn't right as x should be less thsn -1.
Now stmt 2 rules out x = 3 as a possibility.
So the correct ans is x= 1/3 and c.
stmt 1 :: | x + 1 | = 2 | x - 1 |
if x>1 :: x+1 = 2x - 2 => x =3.
if -1 < x <1> x = 1/3.
if x<1> x = 3. This solution isn't right as x should be less thsn -1.
Now stmt 2 rules out x = 3 as a possibility.
So the correct ans is x= 1/3 and c.
"To do is to be"
- blue_lotus
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Hi,
A)
When you have Modulus on both side, I use a simpler approach
Square both sides, this removes any sign issues
(x+1)^2 = [2(x-1)]^2
x^2 + 2x + 1 = 4( x^2 - 2x + 1)
x^2 + 2x + 1 = 4 x^2 - 8x + 4
0 = 3x^2 - 10x +3
0 = 3x^2 - 9x - 1x +3
0 = 3x(x-3) -1(x -3)
0 = (x-3)( 3x-1)
=> (3x-1)= 0 or (x-3)=0
i.e x =1/3 or x = 3
not sufficient
B)|x-3| not equal to 0
means x not equal to 3
not sufficient
But comining A and B we see that x = 1/3 which is sufficient
answer is C
A)
When you have Modulus on both side, I use a simpler approach
Square both sides, this removes any sign issues
(x+1)^2 = [2(x-1)]^2
x^2 + 2x + 1 = 4( x^2 - 2x + 1)
x^2 + 2x + 1 = 4 x^2 - 8x + 4
0 = 3x^2 - 10x +3
0 = 3x^2 - 9x - 1x +3
0 = 3x(x-3) -1(x -3)
0 = (x-3)( 3x-1)
=> (3x-1)= 0 or (x-3)=0
i.e x =1/3 or x = 3
not sufficient
B)|x-3| not equal to 0
means x not equal to 3
not sufficient
But comining A and B we see that x = 1/3 which is sufficient
answer is C