不知道有几个人看了John Hull的那本《options futures and other derivatives》(fifth edition)
在Page 47，3.6节中  
在已知债券现金收入的条件下计算买卖债券远期合约净利润。

题目：已知付息债券价格900，而远期合约为930，假定远期合约1年后到期，而债券是5年期的，息票半年一付，每次固定为40，同时假定半年无风险利率9%（复利，年化率）和一年的为10%。
那么，如果一个套利者买入债券，并卖出远期合约，那么套利者的利润为多少？



他书上的解法，看不太明白，望哪位看过的给个解释。

计算过程原文：The first coupon payment has present value of 40e（-0.09*0.5 此处为幂指数）=38.24. Of the 900,38.24 si therefore borrowed at 95% per annum for sit months so that it can be repaid with the first coupon payment. The remaining 861.76 is borrowed at 10% per annum for one year. the amount owing at he end of the year is 861.76e（0.1*1）=952.39. The second coupon provides 40 toward this amount ,and 930 is received for the bond under the terms of the forward contract. the arbitrateur therefore makes a net profit of:
40+930-952.39=17.61

我个人觉得，这个计算过程，看不太明白，一会计算当前值，一会计算未来值。。