a) Px= 2x^2+2x - 6x^2+ 4x^3 + 2 - x^3
=2x^2+2x +(-6x^2)+4x^3+2+(-x^3)
=[2x^2+(-6x^2)]+2x + [4x^3 + (-x^3)]+2
= -4x^2 + 2x + 3x^3 +2
sắp xếp:
3x^3 - 4x^2 + 2x + 2
Qx= 3 - 2x^4 + 3x + 2x^4+ 3x^3 - x
= 3 + (-2x^4)+ 3x + 2x^4 + 3x^3 + (-x)
= 3+[(-2x4)+ 2x^4] + [3x + (-x)] +3x^3
=3+2x+3x^3
sắp xếp:
3x^3+2x+3
b) Cx= Px+Qx
Px= 3x^3 - 4x^2 + 2x + 2
+
Qx= 3x^3 - + 2x + 3
= 6x^3 - 4x^2 + 4x + 5
C) Dx= Qx-Px
Qx= 3x^3 + 2x + 3
Px= 3x^3 - 4^2 + 2x + 2
Dx=Qx-Px=4x^2 + 1