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zagcollins
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PostPosted: Mon Jul 21, 2008 6:46 am    Post subject: Rooted! Reply with quote
Stuck after a certain pt..I need to devise new ways to tackle problems and not get bogged down...grrrrr Evil or Very Mad
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louvre
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PostPosted: Mon Jul 21, 2008 7:21 am    Post subject: Reply with quote
I think it's 4!
Oh My...took really long to solve.
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zagcollins
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PostPosted: Mon Jul 21, 2008 7:31 am    Post subject: Reply with quote
the answer is 4..can you please post a detailed explanation of the same?
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kris610
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PostPosted: Mon Jul 21, 2008 7:53 am    Post subject: Reply with quote
zagcollins wrote:
the answer is 4..can you please post a detailed explanation of the same?


First take the right side of the given equation: (2/(8+sqrt(63)). Multiply both the numerator and denominator by (8-sqrt(63)) and then add the left side in the equation (2+sqrt(63)). You will see that this term cancels out and you will be left with sqrt(16).

It will be pretty easy when you actually solve this on paper.
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zagcollins
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PostPosted: Mon Jul 21, 2008 8:03 am    Post subject: Reply with quote
still don't get it...grrrrr...
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sudhir3127
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PostPosted: Mon Jul 21, 2008 8:04 am    Post subject: Reply with quote
Sq root ( 2rsqt63 + 2/(8+3sqrt7) )

sq rt ( 2* sqrt (9*7) + 2/(8+3sqrt7) )... ( 63 can be written as 9*7)

sq rt ( 6 sqrt7 + 2 / (8+3sqrt7) )

lcm is 8+3sqrt7

sq root ( 48 sqrt 7 + 126 + 2 ) /(8+3sqrt7)

sqroot ( 16 ( 3 sqrt7 + 8 ) / (8+3sqrt7))

which is equal to sqroot (16)

hence 4.

hope this is clear.
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zagcollins
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PostPosted: Mon Jul 21, 2008 9:38 am    Post subject: Reply with quote
thanks sudhir...now its clearer..solved it myself this time...
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