In country Zeta, only one-year and two-year bonds exist. Investors, who do care about risk, ask for a risk premium to hold the two-year bond (which is risky, as they do not know the price at which they will be able to sell it in a year). Use the arbitrage equation to derive the (approximate) relation that will hold in this case among the yield to maturity of a two-year bond (2), the current (1) and future expected (1,+1) yields on one-year bonds, and the risk premium ().