  This work considers a stochastic model in which the uncertainty is driven by
a multidimensional Brownian motion. The market price of risk process makes the
transition between real world probability measure and risk neutral probability
measure. Traditionally, the martingale representation formulas under the risk
neutral probability measure requires the market price of risk process to be
bounded. However, in several financial models the boundedness assumption of the
market price of risk fails. One example is a stock price model with the market
price of risk following an Ornstein-Uhlenbeck process. This work extends
Clark-Haussmann formula to underlying stochastic processes which fail to
satisfy the standard requirements. Our result can be applied to hedging and
optimal investment in stock markets with unbounded market price of risk.
