The coefficient of in the expansion of is

MATHEMATICS · Subjective · A Level · Mathematics · Sequences and series · Sequences and series

Problem

The coefficient of

x^{8}

in the expansion of

(x+2/x)^{n}

264

. (i) Obtain an equation connecting

n

and the integer

r

corresponding to the term that contains

x^{8}

. (ii) Using the binomial coefficient, write the numerical value of the coefficient in terms of

n

and

r

. (iii) Hence determine the value of

n