[tex]1. \\ \\(2x^3y^3)(5x^2y^8) =2\cdot 5\cdot x^{3+2}\cdot y^{3+8} =10 \cdot x^{5}\cdot y^{11} \\ \\ 2.\\ \\ 9b^3(8b^4)(-b) =-9\cdot 8\cdot b^{3+4+1} =-72\cdot b^{8}[/tex]
[tex]3.\\ \\ 3y^2(y^2-2y+3)=\\ \\=3y^2\cdot y^2-3y^2\cdot 2y+3y^2\cdot 3 =\\ \\ =3y ^{2+2} -6y ^{2+1} +9y^2 =\\ \\= 3y ^{4} -6y ^{3} +9y^2[/tex]
[tex]4.\\ \\ (x + 3)(x-2)=x^2-2x+3x-6 = x^2+x-6[/tex]