Odpowiedź:
[tex]a)\ \ (6+x)(2x+1)=12x+6+2x^2+x=2x^2+13x+6\\\\\\b)\ \ (3t-7)(t-2)=3t^2-6t-7t+14=3t^2-13t+14\\\\\\c)\ \ (xy-x)(3xy+5x)=3x^2y^2+5x^2y-3x^2y-5x^2=3x^2y^2+2x^2y-5x^2\\\\\\d)\ \ (2a-1)^2=(2a)^2-2*2a*1+1^2=4a^2-4a+1\\\\\\e)\ \ (3m-1)(-m^2+2m-2)=-3m^3+6m^2-6m+m^2-2m+2=\\\\=-3m^3+7m^2-8m+2\\\\\\f)\ \ (2y+1)(y-3)-2y(3-y)=2y^2-6y+y-3-6y+2y^2=4y^2-11y-3[/tex]
