Let's simplify the expression step by step:
X(x+2)(x-2) = X(x^2 - 2x + 2x - 4) = X(x^2 - 4)
(x-3)(x^2 + 3x + 9) = x(x^2 + 3x + 9) - 3(x^2 + 3x + 9)= x^3 + 3x^2 + 9x - 3x^2 - 9x - 27= x^3 - 27
X(x^2 - 4) - (x^3 - 27)= Xx^2 - 4X - x^3 + 27= - x^3 + Xx^2 - 4X + 27
Therefore, the simplified expression is - x^3 + Xx^2 - 4X + 27.
Let's simplify the expression step by step:
Expand the first set of parentheses:X(x+2)(x-2) = X(x^2 - 2x + 2x - 4) = X(x^2 - 4)
Expand the second set of parentheses:(x-3)(x^2 + 3x + 9) = x(x^2 + 3x + 9) - 3(x^2 + 3x + 9)
Subtract the second expression from the first one:= x^3 + 3x^2 + 9x - 3x^2 - 9x - 27
= x^3 - 27
X(x^2 - 4) - (x^3 - 27)
= Xx^2 - 4X - x^3 + 27
= - x^3 + Xx^2 - 4X + 27
Therefore, the simplified expression is - x^3 + Xx^2 - 4X + 27.