Find the coefficient of x^-3 in the expansion of `(x -1/(2x))^5`

Find the coefficient of x^-20 in the expansion of (x^3 - 1/(2x^2))^15 .

Find the coefficient of x^4 in the expansion of (x^2 - (2/x))^8

Find the coefficient of x^3 in the expansion of (2x + (1/3x^2))^9

Find the coefficient of x^6 in the expansion of (3x^2 - 1/ (3x))^9

Find the coefficient of x^-17 in the expansion of (x^4 - (1/x^3))^15

Find the coefficient of x^17 in the expansion of (3x - (x^3/6))^9

Find the coefficient of x^7 in the expansion of (x^(2) +1/x)^(11)

Find the coefficient of x^9 in the expansion of (1/x + x^2)^18

Find the coefficient of : (i) x^3 in the expansion of (1 - x)^(-1/4) (ii) x^2 in the expansion of (5 - 3x)^(-1/3)