Devi applicare la proprietà distributiva:
(x^2 - 3x + 4) * ( x - 1/2) =
= x^3 - 1/2 x^2 - 3x^2 + 3/2 x + 4x - (4 * 1/2) =
= x^3 - 1/2 x^2 - 3x^2 + 3/2 x + 4x - 2 =
= x^3 - 1/2 x^2 - 6/2 x^2 + 3/2 x + 8/2x - 2 =
= x^3 - 7/2 x^2 + 11/2 x - 2.
Ciao @giuly123
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$\left(x^2-3x+4\right)\left(x-\dfrac{1}{2}\right)=$
$= x^3-\dfrac{1}{2}x^2-3x^2+\dfrac{3}{2}x+4x-\dfrac{\cancel4^2}{\cancel2_1}=$
$= x^3+\dfrac{-1-6}{2}x^2+\dfrac{3+8}{2}x-2=$
$= x^3-\dfrac{7}{2}x^2+\dfrac{11}{2}x-2$