Saturation polarization at Curie point in a first-order transition the equilibrium condition (43) with T set equal to T, gives one equation for the polarization P_s (T_c). A further condition at the Curie point is that F(P_s T_c) = F(0, T_c). 

(a) Combining these two conditions, show that P²_s (T_c) = 3/g_4|/4g₆. 

(b) Using this result, show that T_c = T₀ + 3g²₄/16yg⁶.