For this question, I would first explain that this is an algebraic expansion question. To write the equation in the form asked, it would be easier to expand two brackets at a go. I would take this opportunity to write on the whiteboard, (x+1) x (x+2) which would give x^2 + 3x +2. I would also explain how I came to that answer through each multiplication within the bracket.Thereafter, the answer we got previously should be multiplied by (x+3). This will be given by(x^2+3x+2) x (x+3) = x^3+5x^2+8x+6. Through normal expansion methods. I would again explain how I came to that answer through each multiplication within the bracket.