Simplify the following expression. $(2x - 3y)^3 - 18 xy (2x - 3y)$

$8x^3 - 72x^2y + 108 xy^2- 27 y^3$

We have to solve $(2x - 3y)^3 - 18 xy (2x - 3y)$

Put x = y = 1, ( These value will satisfy the given equations)

Value of the expression = (2 × 1 - 3 × 1)³ - 18(2 × 1 - 3 × 1)

= -1 - 18(-1)

= -1 + 18 = 17

If we check option (2),

8(1) - 72(1) + 108(1) - 27(1)

= 116 - 99 = 17

So the answer is = $8x^3 - 72x^2y + 108 xy^2- 27 y^3$