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In thermodynamics, there is a function which, for the three variables x, y, and z, can be given as
##G = xG_x+yG_y+zG_z + N[x\ln(x) + y\ln(y)+ z\ln(z)]+E(x,y,z)##
where G_x, G_y, G_z, and N are some constants and E is some arbitrarily complicated term.
There is a...