Odpowiedź:
P+Q = [tex]7x^{3} -3x^{2} y+2xy-5y[/tex]
P - Q = [tex]-3x^{3} -9x^{2} y+6xy-y[/tex]
Szczegółowe wyjaśnienie:
[tex]P=2x^{3}-6x^{2} y+4xy-3y[/tex]
[tex]Q= 5x^{3} +3x^{2} y-2xy-2y[/tex]
P+Q = [tex]( 2x^{3}-6x^{2} y+4xy-3y) +[/tex] [tex](5x^{3} +3x^{2} y-2xy-2y)[/tex] =
= [tex]7x^{3} -3x^{2} y+2xy-5y[/tex]
P - Q = [tex]( 2x^{3}-6x^{2} y+4xy-3y) -[/tex][tex](5x^{3} +3x^{2} y-2xy-2y)[/tex] =
= [tex]2x^{3}-6x^{2} y+4xy-3y -[/tex] [tex]5x^{3} -3x^{2} y+2xy+2y[/tex] =
= [tex]-3x^{3} -9x^{2} y+6xy-y[/tex]
