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