b: \(=\left(2x-3\right)\left(3y-2\right)-\left(2x-3\right)\left(y+1\right)\)
\(=\left(2x-3\right)\left(3y-2-y-1\right)=\left(2x-3\right)\left(2y-3\right)\)
j: \(=x^2\left(x-y-2\right)-4\left(x-y-2\right)\)
\(=\left(x-y-2\right)\left(x^2-4\right)\)
\(=\left(x-y-2\right)\left(x-2\right)\left(x+2\right)\)
