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#1 2007-10-14 11:21:20
- simone
- Member
- Registered: 2007-10-05
- Posts: 19
algebra help
Hi, could you please help me solve this question? Thank you!
If x and y are positive, which of the following must be greater than 1/sqrt(x+y) ?
1) (sqrt(x+y))/(2x)
2) (sqrt(x)+sqrt(y))/(x+y)
2) (sqrt(x)-sqrt(y))/(x+y)
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#2 2007-10-14 13:01:39
- JaneFairfax
- Member
- Registered: 2007-02-23
- Posts: 6,868
Re: algebra help
So the middle one is true. The others are false; you can easily find counterexamples.
Last edited by JaneFairfax (2007-10-14 13:11:35)
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#3 2007-10-14 20:44:29
- simone
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- Registered: 2007-10-05
- Posts: 19
Re: algebra help
thank you so much Jane.
Last edited by simone (2007-10-14 20:44:49)
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