lets expand the first two brackets first, so x * x gives x2, x * 2 gives 2x, x * 1 gives x and 1 * 2 = 2. 2x and x are both in terms of x so we add these together to get 3x, giving us the quadratic (x2 + 3x + 2). now we expand this bracket with (x +3). x2 * x = x3x2 * 3 = 3x2 3x * x = 3x2 3x * 3 = 9x 2 * x = 2x 2 * 3 = 6 then when we add all the like terms together we get x3+ 6x2+ 11x + 6 so a=1, b=6, c=11 and d= 6