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Old 2004-04-27, 03:18   #7
wblipp
 
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"William"
May 2003
New Haven

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Quote:
Originally Posted by jinydu
Anyway, here's the challenge. Prove that

cube root(10+sqrt(108)) + cube root(10-sqrt(108)) = 2
(1+sqrt(3))^3 = 10+sqrt(108)
(1-sqrt(3))^3 = 10-sqrt(108)

So the expression is
1+sqrt(3)+1-sqrt(3) = 2

William
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