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How to do this mc question? (1 Viewer)

malcolm21

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Can someone help me with this question too:

Use the binomial theorem to find an expression for the constant term
in the expansion of (2x^3 - 1/x)^12

Im very weak with the last two topics motion and binomial
 

InteGrand

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Can someone help me with this question too:

Use the binomial theorem to find an expression for the constant term
in the expansion of (2x^3 - 1/x)^12

Im very weak with the last two topics motion and binomial










 

kawaiipotato

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Tk+1 = (n k) (2x^3)^12-k (-x^-1)^k
Find coeff of x^0
Or alternatively collect the fraction together
= (2x^4 - 1)^12 / x^12
and use the general term to find x^12 at the top as x^12 / x^12 gives the constant term
 

SNT k

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They probably wont ask that though, most likely a binominal proof of some sort.
 

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