\(7,=\dfrac{2+x-1+x+1}{2\left(x-1\right)\left(x+1\right)}=\dfrac{2\left(x+1\right)}{2\left(x-1\right)\left(x+1\right)}=\dfrac{1}{x-1}\\ 8,=\dfrac{3x+2+13}{\left(x+5\right)\left(3x+2\right)}=\dfrac{3\left(x+5\right)}{\left(x+5\right)\left(3x+2\right)}=\dfrac{3}{3x+2}\\ 9,=\dfrac{6x+5x+15+3x-9}{\left(x-3\right)\left(x+3\right)}=\dfrac{14x+6}{\left(x-3\right)\left(x+3\right)}\)
7: \(=\dfrac{2+x-1+x+1}{2\left(x+1\right)\left(x-1\right)}=\dfrac{2x+2}{2\left(x+1\right)\left(x-1\right)}=\dfrac{1}{x-1}\)