1/(5-2 square root 8) - 1/(5+2square root 8)=??
Does some one can help me this question!?
OA is -4 square root 8/7
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Solution:
1/[5 - 2*sqrt(8)] = (5+2*sqrt(8))/[(5 - 2*sqrt(8))*(5 + 2*sqrt(8)] = (5+2*sqrt(8))/(25 - 32) = -(5+2*sqrt(8))/7. (multiplying both numerator and denominator by (5+2*sqrt(8))
Also 1/(5+2*square root 8) = (5 - 2*sqrt(8))/[(5 - 2*sqrt(8))*(5 + 2*sqrt(8)] =
(5 - 2*sqrt(8))/(25 - 32) = -(5- 2*sqrt(8))/7. (multiplying both numerator and denominator by (5 - 2*sqrt(8))
So 1/[5 - 2*sqrt(8)] - 1/(5+2*square root 8) = -(5+2*sqrt(8))/7 + (5- 2*sqrt(8))/7 = -(4*sqrt(8))/7.
1/[5 - 2*sqrt(8)] = (5+2*sqrt(8))/[(5 - 2*sqrt(8))*(5 + 2*sqrt(8)] = (5+2*sqrt(8))/(25 - 32) = -(5+2*sqrt(8))/7. (multiplying both numerator and denominator by (5+2*sqrt(8))
Also 1/(5+2*square root 8) = (5 - 2*sqrt(8))/[(5 - 2*sqrt(8))*(5 + 2*sqrt(8)] =
(5 - 2*sqrt(8))/(25 - 32) = -(5- 2*sqrt(8))/7. (multiplying both numerator and denominator by (5 - 2*sqrt(8))
So 1/[5 - 2*sqrt(8)] - 1/(5+2*square root 8) = -(5+2*sqrt(8))/7 + (5- 2*sqrt(8))/7 = -(4*sqrt(8))/7.
Rahul Lakhani
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Gurome, Inc.
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On MBA sabbatical (at ISB) for 2011-12 - will stay active as time permits
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Quant Expert
Gurome, Inc.
https://www.GuroMe.com
On MBA sabbatical (at ISB) for 2011-12 - will stay active as time permits
1-800-566-4043 (USA)
+91-99201 32411 (India)
