Question

(i) Find the value of r, if the coefficients of (2r + 2)th and (r-2)th terms in the expansion of (1+x)^{18} are equal.

(ii) Find the coefficient of $x^{-}17$ in the expansion of ${(x^4-\frac{1}{x^3})}^{15}$

(iii) Find the term independent of x in the expansion of ${(2x-\frac{1}{x})}^{10}$

Answer 1

(i) r = 6

(ii) -1365

(iii) x = - 8064