a) $A(x)= 2x^3–2x+x^2–x^3+3x+2$
$=(2x^3-x^3)+(-2x+3x)+x^2+2$
$=x^3+x+x^2+2$
$B(x)=4x^3–5x^2+3x–4x–3x^3+4x^2+1$
$=(4x^3-3x^3)+(-5x^2+4x^2)-x+1$
$=x^3-x^2-x+1$
b) $A(x)+B(x)=(x^3+x+x^2+2)+(x^3-x^2-x+1)$
$=(x^3+x^3)+(x-x)+(x^2-x^2)+(2+1)$
$=2x^3+3$
c) $*)A(1)=2.1^3+3=5$
$*)B(-2)=2.(-2)^3+3=-13$
xin hay nhất