9.11 Boundary-layer separation occurs when the shear stress at the surface becomes zero. Assume that a polynomial representation for the laminar boundary layer of the form, u U =a+bλ +cλ2 +dλ3, where λ=y δ. Specify boundary conditions on the velocity profile at separation. Find appropriate constants,

a, b,

c, and

d, for the separation profile. Calculate the shape factor H at separation. Plot the profile and compare with the parabolic approximate profile.