479)
6/x+6/(x+1)=5
5x² +5x=6x+6+6x
5x² -7x -6 =0
x₁=(7+sqrt(49+120)/(2*5) =(7+sqrt(169))/10=(7+13)/10 =20/10= 2
x₂=(7-sqrt(49+120)/(2*5) =(7-sqrt(169))/10=(7- 13)10 =(-6/)10= - 0,6
115) (2a+2b)/b*(1/(a-b)-1/(a+b)) = 2(a+b)/b*(a+b-(a-b))/(a-b)(a+b)=
=2(a+b)/b*2b/(a-b)(a+b) = 4/(a-b)