As an alternative approach to derive the value of a European floating strike lookback call, we consider 

where S_t = S,m^t _T0 = m and τ = T − t. We may decompose the above expectation calculation into two terms:

 Show that the first term is given by

Now, the second term can be expressed as 

By performing the tedious integration procedure, show that the same price function for c_fℓ (S,m,τ) [see (4.2.9)] is obtained.