If Sum Of The Coefficients Of x7 and x4 in The Expansion Of 

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Question

If sum of the coefficients of x7 and x4 in the expansion of 

Solution

Correct option is

ab = 1

         

For the coefficient of x7 set 22 – 3r = 7 or r = 5 for the coefficient of x4r= 6.

SIMILAR QUESTIONS

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Q3

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Q4

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Q7

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Q8

 

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Q9

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Q10

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