From the given responses, find the missing letter in

If 27x³ - 8y³ = (3x - Ay) X (Bx² + 4y² + Cxy), then find the value of 3 X (2A + 6B) - 2C.

Solve the inequality:

(x − 1)/(x + 2) > 2.

Which of the following represents the solution set?

(A) x < −5

If x – 1/x = 9, then x³ – 1/x³ is:

If  x = a(b - c), y = b(c – a) and z = c(a - b) , find the value of  (x/a)³ + (y/b)³ + (z/c)³?

If, ( a + b = 14 ) and ( a² + b² = 106 ), then find the value of (a³ + b³).

What will come in place of the question mark (?) in the following series?

23, 46, ?, 184, 368, 736

If x = 19, then the value of x⁵ - 20x⁴ + 20x³ - 20x² + 20x - 1 is

If √k + (1/√k) = 8, then find the value of k + (1/k).