Tìm đa thức C ( x ) biết ( 2 x + 1 ) . C ( x ) = A ( x ) .

b) Ta có: \(\left( {2x + 1} \right).C\left( x \right) = A\left( x \right)\) nên \(C\left( x \right) = A\left( x \right):\left( {2x + 1} \right)\).

Suy ra \(C\left( x \right) = \left( {2{x^3} - 3{x^2} + 4x + 3} \right):\left( {2x + 1} \right) = {x^2} - 2x + 3\).

Vậy \(C\left( x \right) = {x^2} - 2x + 3\).