[tex]zad.1\\\\POZIOM~~A\\\\a)~~(x-4)\cdot (x-2)=x^{2} -2x-4x+8=x^{2} -6x+8\\\\b)~~(3k-2)\cdot (k-4)=3k^{2} -12k-2k+8=3k^{2} -14k+8\\\\c)~~(2m-1)\cdot (m+1)=2m^{2} +2m-m-1=2m^{2} +m-1\\\\POZIOM~~B\\\\a)~~(2b+a)\cdot (3-b)=6b-2b^{2} +3a-ab\\\\b)~~(-x+3xy)\cdot (3-b)=-3x+bx+9xy-3bxy\\\\c)~~(st-3)\cdot (5+st)=5st+s^{2} t^{2} -15-3st=s^{2} t^{2}+2st-15[/tex]
