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If xy ≠ 0 and 1/x - 1/y =cx, which of the following is equal
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16 Jun 2020, 03:30
16 Jun 2020, 03:30
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Question Stats:
93% (00:35) correct
6% (02:52) wrong based on 30 sessions
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If \(xy ≠ 0\) and \(\frac{1}{x} - \frac{1}{y} =cx\), which of the following is equal to c ?
A. \(\frac{x}{y(1 - x^2)}\)
B. \(\frac{1}{-x^2y}\)
C. \(\frac{y - x}{x^2y}\)
D. \(\frac{y - x}{y}\)
E. \(\frac{y}{y - x}\)
A. \(\frac{x}{y(1 - x^2)}\)
B. \(\frac{1}{-x^2y}\)
C. \(\frac{y - x}{x^2y}\)
D. \(\frac{y - x}{y}\)
E. \(\frac{y}{y - x}\)
Re: If xy ≠ 0 and 1/x - 1/y =cx, which of the following is equal
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16 Jun 2020, 03:30
16 Jun 2020, 03:30
Expert Reply
Post A Detailed Correct Solution For The Above Questions And Get A Kudos.
Question From Our New Project: GRE Quant Challenge Questions Daily - NEW EDITION!
Question From Our New Project: GRE Quant Challenge Questions Daily - NEW EDITION!
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Re: If xy ≠ 0 and 1/x - 1/y =cx, which of the following is equal
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16 Jun 2020, 05:21
16 Jun 2020, 05:21
Carcass wrote:
If \(xy ≠ 0\) and \(\frac{1}{x} - \frac{1}{y} =cx\), which of the following is equal to c ?
A. \(\frac{x}{y(1 - x^2)}\)
B. \(\frac{1}{-x^2y}\)
C. \(\frac{y - x}{x^2y}\)
D. \(\frac{y - x}{y}\)
E. \(\frac{y}{y - x}\)
A. \(\frac{x}{y(1 - x^2)}\)
B. \(\frac{1}{-x^2y}\)
C. \(\frac{y - x}{x^2y}\)
D. \(\frac{y - x}{y}\)
E. \(\frac{y}{y - x}\)
Given: \(\frac{1}{x} - \frac{1}{y} =cx\)
Multiply both sides \(\frac{1}{x}\) by to get: \((\frac{1}{x})(\frac{1}{x} - \frac{1}{y}) = (\frac{1}{x})(cx)\)
Expand and simplify to get: to get: \(\frac{1}{x^2} - \frac{1}{xy} = c\)
Check the answer choices... not there!
Looks like we need to rewrite the left side as one entire fraction
Rewrite with common denominators to get: \(\frac{y}{x^2y} - \frac{x}{x^2y} = c\)
Combine: \(\frac{y - x}{x^2y} = c\)
Answer: C
Cheers,
Brent
