2.2~2.6

2.4. Establish (2.6) (a) by setting up suitable portfolios and applying the argu- ments used to get (2.4)-(2.5), and (b) separately, by using (2.4)-(2.5) plus put-call parity (2.2). 2.4. Establish (2.6) (a) by setting up suitable portfolios and applying the argu- ments used to get (2.4)-(2.5), and (b) separately, by using (2.4)-(2.5) plus put-call parity (2.2)