\(A=2x^2-3y^3-z^4-4x^2+2y^4+3z^4\\ =-2x^2-y^2+2z^4\\ =2\left(z^4-x^2\right)-y^2\)
\(B=2x^2y-5xy^2+4x^2y-6xy^2\\ =6x^2y-11xy^2\\ =xy\left(6x-11y\right)\)
A=2x2−3y3−z4−4x2+2y4+3z4
=−2x2−y2+2z4
=2(z4−x2)−y2
B=2x2y−5xy2+4x2y−6xy2
=6x2y−11xy2
=xy(6x−11y)