Cześć!
Zadanie 2
a)
[tex](x-5)(x-2)+(2-x)(x-3)=\\\\=x^2-2x-5x+10+(2x-6-x^2+3x)=\\\\=x^2-7x+10+(-x^2+5x-6)=x^2-7x+10-x^2+5x-6=\\\\=x^2-x^2-7x+5x+10-6=\boxed{-2x+4}[/tex]
b)
[tex](x+2)(x+3)(x+4)=(x^2+3x+2x+6)(x+4)=\\\\=(x^2+5x+6)(x+4)=x^3+4x^2+5x^2+20x+6x+24=\boxed{x^3+9x^2+26x+24}[/tex]
Zadanie 3
a)
[tex]4-\frac{1}{2}(10x-8)=2x-12\\\\4-5x+4=2x-12\\\\-5x-2x=-12-4-4\\\\-7x=-20 \ \ /:(-7)\\\\x=\frac{20}{7}\\\\\boxed{x=2\frac{6}{7}}[/tex]
b)
[tex](3x-2)(6x-1)=(2x+6)(9x+1)\\\\18x^2-3x-12x+2=18x^2+2x+54x+6\\\\18x^2-15x+2=18x^2+56x+6\\\\18x^2-15x-18x^2-56x=6-2\\\\-71x=4 \ \ /:(-71)\\\\\boxed{x=-\frac{4}{71}}[/tex]
