Section 26.9 gives two formulas for a down-and-out call. The first applies to the situation where the

Question:

Section 26.9 gives two formulas for a down-and-out call. The first applies to the situation where the barrier, H, is less than or equal to the strike price, K. The second applies to the situation where H ≥ K. Show that the two formulas are the same when H = K.