Explain the benefits of sustainable practices to an individual firm. Solution Public relations: If publicised, sustainable practices can be a good source of public relations which can help promote a firm, its brand and its products. Cost effective: Sustainable practices discourage waste and so can be a means of containing or even reducing costs. Good CSR: Sustainable practices are ways of demonstrating social responsibility and so might form part of a firm.

1. Explain the binomial theorem. Express and list out the following theorem.
(x + y)4 where is a constant
Solution
Try multiplying it out as follows, and you will see that the 1,4,6,4,1 pattern appears naturally:
(x+y)1 = x + y
(x+y)2 = (x+y)*(x+y) = x2+xy+xy+y2 = x2 + 2xy + y2
(x+y)3 = (x2+2xy+y2)*(x+y) = x3+2x2y+xy2+x2y+2xy2+y3 = x3 + 3x2y + 3xy2 + y3
and finally:
(x+y)4 = (x3+3x2y+3xy2+y3)*(x+y) = x4+3x3y+3x2y2+y3x+x3y+3x2y2+3xy3+y4 = x4 +
4x3y + 6x2y2 + 4xy3 + y4