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Binomial help (: (1 Viewer)
- Thread starter Aysce
- Start date
RishBonjour
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- 2012
did you get the RHS bit?
For the left hand side--> looking for coeff of x^2. first 2 terms don't have any. But for everything else, It seems like we consider them seperately and extract coeff of x^2 from each and that gives you that pattern.
e.g. for (1+x )^10
coeff of x^2 is 10C2 (x^2)
For the left hand side--> looking for coeff of x^2. first 2 terms don't have any. But for everything else, It seems like we consider them seperately and extract coeff of x^2 from each and that gives you that pattern.
e.g. for (1+x )^10
coeff of x^2 is 10C2 (x^2)
Following on from RishBonjour.....
Expand the RHS first using binomial theorem (ie. the first term). Every term in the expansion would be divided by x, so the general term becomes n+1Ck times x^(k-1).
From here, consider the term in x^2 on the RHS: ie k - 1 = 2
therefore, the value of k is 3, which gives you the required coefficient.
Hope this helps.
Expand the RHS first using binomial theorem (ie. the first term). Every term in the expansion would be divided by x, so the general term becomes n+1Ck times x^(k-1).
From here, consider the term in x^2 on the RHS: ie k - 1 = 2
therefore, the value of k is 3, which gives you the required coefficient.
Hope this helps.