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Blazing goIITian

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9 Aug 2010 00:31:51 IST

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do it , if alpha beta gama are the rootsof x^3-x-1=0 then 1+alpha/1-alpha+1+beta/1

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do it , if alpha beta gama are the rootsof x^3-x-1=0 then 1+alpha/1-alpha+1+beta/1-beta+1+gama/1-gama=

Comments (6)

krishna kamal

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Joined: 18 Jul 2010

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12 Aug 2010 06:22:44 IST

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answer is very simple.answer=-1/3

Radhika avasthi

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Joined: 9 Aug 2010

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13 Aug 2010 00:42:29 IST

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just simplyfy the whole thing and use the summation and products of roots........As simple as it seems to be.....

rahulmishra

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14 Aug 2010 11:37:01 IST

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Someone please solve!!!!!!!!!!!!!!!!!!!!!!

rahulmishra

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14 Aug 2010 11:41:48 IST

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clearly, alpha + beta + gama = 0 ------ (i)

alpha² + beta² + gama² = -1

alpha x beta + beta x gama + gama x alpha = -1

alpha x beta x gama = 1
So,on dividing alpha x beta + beta x gama + gama x alpha by alpha x beta x gama we get,

1/alpha + 1/beta + 1/gama = -1

Adding 3 to both the sides we get

(1 + alpha)/alpha + (1 + beta)/beta + (1 + gama)/gama = 2

But what next to do??????????

saurav

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Joined: 30 May 2010

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15 Aug 2010 13:31:44 IST

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use trasformation of eqns read bs grewal for details

Hari Shankar

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Joined: 28 Feb 2007

Posts: 2185

17 Aug 2010 16:50:49 IST

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