Cho các đa thức C=x^3+4x^3y-6xy^3-4xy^2+5x^2y^2
Giải thích
C−A−B
=x3+4x3y−6xy3−4xy2+5x2y2−5x3y−4xy2−6x2y2−−8xy3+xy2−4x2y2
=x3+4x3y−6xy3−4xy2+5x2y2−5x3y+4xy2+6x2y2+8xy3−xy2+4x2y2
=x3−x3y+2xy3−xy2+15x2y2
C−A−B
=x3+4x3y−6xy3−4xy2+5x2y2−5x3y−4xy2−6x2y2−−8xy3+xy2−4x2y2
=x3+4x3y−6xy3−4xy2+5x2y2−5x3y+4xy2+6x2y2+8xy3−xy2+4x2y2
=x3−x3y+2xy3−xy2+15x2y2