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If r > 0, s ≠ 1/2 and r = 3s +1/1-2s, then s=
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Updated on: 27 Dec 2018, 03:22
Updated on: 27 Dec 2018, 03:22
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Question Stats:
86% (01:27) correct
13% (02:15) wrong based on 269 sessions
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If \(r > 0\), s ≠ \(\frac{1}{2}\) and \(r = \frac{3s +1}{1-2s}\), then \(s=\)
A) \(\frac{3r}{12 +6r}\)
B) \(-\frac{2r}{3}\)
C) \(\frac{r-1}{3+2r}\)
D) \(\frac{2}{3} (1-r)\)
E) \(-\frac{1+r}{3}\)
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Re: If r > 0, s ≠ 1/2 and r = 3s +1/1-2s, then s=
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15 Jun 2017, 13:41
15 Jun 2017, 13:41
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Carcass wrote:
If \(r > 0\), s ≠ \(\frac{1}{2}\) and \(r = \frac{3s +1}{1-2s}\), then \(s=\)
A) \(\frac{3r}{12 +6r}\)
B) \(\frac{-2r}{3}\)
C) \(\frac{r-1}{3+2r}\)
D) \(\frac{2}{3(1-r)}\)
E) \(\frac{-1+r}{3}\)
Given: \(r = \frac{3s +1}{1-2s}\)
Multiply both sides by (1 - 2s) to get: r(1 - 2s) = 3s + 1
Expand: r - 2rs = 3s + 1
NOTE: We want the s's on one side. So....
Add 2rs to both sides: r = 3s + 2rs + 1
Subtract 1 from both sides: r - 1 = 3s + 2rs
Factor right side: r - 1 = s(3 + 2r)
Divide both sides by (3 + 2r) to get: (r - 1)/(3 + 2r) = s
Answer:
Show: ::
C
Cheers,
Brent
Re: If r > 0, s ≠ 1/2 and r = 3s +1/1-2s, then s=
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02 May 2020, 03:08
02 May 2020, 03:08
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Plug in s = 1 in the RHS and calculate r. Then plug that r value in the options and see which option gives the value of s (1).
When we plug in s, we get 3(1) + 1 / 1 - 2(1) = 4 / -1 = -4.
Plug -4 in the options and see which option gives 1 as the answer.
When we plug in s, we get 3(1) + 1 / 1 - 2(1) = 4 / -1 = -4.
Plug -4 in the options and see which option gives 1 as the answer.
