If x = -1, then (x^4 - x^3 + x^2)/(x-1) =
A) -3/2
B) -1/2
C) 0
D) 1/2
E) 3/2
OA: A
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If x = -1, (OG16)
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boomgoesthegmat
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Hi boomgoesthegmat,
This question is just about making sure that the arithmetic is done correctly (and that we don't lose track of the "minus signs"...
Plugging X = -1 into the given equation, we end up with....
[+1 - (-1) + 1]/[-1 -1] =
[1 + 1 + 1]/[-2] =
[3]/[-2]
Final Answer: A
GMAT assassins aren't born, they're made,
Rich
This question is just about making sure that the arithmetic is done correctly (and that we don't lose track of the "minus signs"...
Plugging X = -1 into the given equation, we end up with....
[+1 - (-1) + 1]/[-1 -1] =
[1 + 1 + 1]/[-2] =
[3]/[-2]
Final Answer: A
GMAT assassins aren't born, they're made,
Rich
Last edited by [email protected] on Fri May 20, 2016 9:45 am, edited 1 time in total.
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OptimusPrep
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In such question, always rememberboomgoesthegmat wrote:If x = -1, then (x^4 - x^3 + x^2)/(x-1) =
A) -3/2
B) -1/2
C) 0
D) 1/2
E) 3/2
OA: A
Even power of negative sign = positive,
Odd power of negative sign = negative.
On plugging x = -1 in (x^4 - x^3 + x^2)/(x-1),
we get (x^4 - x^3 + x^2)/(x-1) = (1 + 1 + 1)/ -2 = -3/2
Correct Option: A
