Algebra

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6 Apr 2012 13:06:26 IST
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Engineering Entrance , JEE Main , JEE Main & Advanced , Mathematics , Algebra

No. of rational terms in the expansion of ((5)^1/5 +(2)^1/2)^10



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hemang's Avatar

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6 Apr 2012 13:38:09 IST
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the r+1 th term in the expansion is C(10,r) * 5^(r/5) * 2^(5-r/2).

so, 2 divides r, 5 divides r, 10 divides r. so r = 0,10.

there are two such terms.

 

 


Blazing goIITian

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6 Apr 2012 14:46:05 IST
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binomial okkkkkkkkkkk

Blazing goIITian

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6 Apr 2012 14:48:45 IST
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yups for r=0,10 the term will be rational when there are TWO rational term i.e. 1st term and last term
sudhindra shenoy's Avatar

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7 Apr 2012 10:46:06 IST
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 answer is 6 isnt it ??  coz     u get rational terms only if u put r=0,2,4,6,8,10 hence no of rational terms is 6.


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7 Apr 2012 10:48:33 IST
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answer is 10
hemang's Avatar

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7 Apr 2012 15:24:27 IST
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the answer can not be 10!!!!!

 




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