Răspuns:
a) E(x) = 3x³-3x³+2x²-4x²-4x+4x-5 = -2x²-5
b) E(x) = 4x²+2x²+4x-6x+4-4 = 6x²-2x
c) E(x) = x²y-x²y-2xy+3xy-3xy²+3xy² = xy
d) E(x) = x³-y³-x²y+x²y+xy²-xy² = x³-y³
e)
[tex]E(x)=3x^{4} y-10x^{4}y +4x^{3} y^{2} -9x^{3} y^{2} +6xy^{4}-7xy^{4} +5x^{2}y^{2} = -7x^{4}y -5x^{3} y^{2} -xy^{4} +5x^{2}y^{2}[/tex]
f) [tex]E(x)=5x^{2} -12x^{2} +6xy-6xy+7y^{2} -7y^{2}+12x^{2} y^{2} -12x^{2} y^{2}+5+2=-7x^{2} +7[/tex]
