1 b)
(\frac{x}{x-3}+\frac{x-5}{(x-3)(x+3)})*(\frac{5}{x-2}-\frac{4}{x-1})=
=\frac{x(x+3)+x-5}{(x-3)(x+3)}*\frac{5(x-1)-4(x-2)}{(x-2)(x-1)}=
D=R-{-3;1;2;3}
=\frac{x^2+3x+x-5}{(x-3)(x+3)}*\frac{5x-5-4x+8}{(x-2)(x-1)}=
=\frac{x^2+4x-5}{(x-3)(x+3)}*\frac{x+3}{(x-2)(x-1)}
…
Obl. pomocnicze
x^2+4x-5=x^2-x+5x-5=x(x-1)+5(x-1)=
=(x-1)(x+5)
,
=\frac{(x-1)(x+5)}{(x-3)(x-2)(x-1)}=\frac{x+5}{(x-3)(x-2)}