Question 43: Simplify the expression: \( A = \left( {{x^2} – 3x + 9} \right)\left( {x + 3} \right) – \left( {54 + {x^) 3}} \right)\)

\(\begin{array}{*{20}{l}} {A = \left( {{x^2} – 3x + 9} \right)\left( {x + 3} \right) – \left ( {54 + {x^3}} \right)}\\ {A = \left( {{x^2} – 3x + {3^2}} \right)\left( {x + 3} \right ) – \left( {54 + {x^3}} \right)}\\ {A = {x^3} + {3^3} – 54 – {x^3}}\\ {A = 27 – 54 = – 27} \end{array}\)