1: \(\dfrac{6x^3-7x^2-x+2}{2x+2}\)
\(=\dfrac{6x^3+6x^2-13x^2-13x+12x+12-10}{2x+2}\)
\(=\dfrac{3x^2\left(2x+2\right)-\dfrac{13}{2}x\left(2x+2\right)+6\left(2x+2\right)-10}{2x+2}\)
\(=3x^2-\dfrac{13}{2}x+6-\dfrac{5}{x+1}\)
2: \(\dfrac{x^2-y^2+6x-9}{x+y+3}\)
\(=\dfrac{x^2-\left(y-3\right)^2}{x+y+3}\)
\(=\dfrac{\left(x-y+3\right)\left(x+y-3\right)}{x+y+3}\)