Total Derivative See Total Derivative f:Rp→Rm and g:Rn→Rp D(f(g(x)))=Df(g(x))Dg(x) 1 dimensional (f(g(x)))′=f′(g(x))⋅g′(x) Flat Multidimensional (f(x(a,b,c),y(a,b,c),z(a,b,c)))c=fxxc+fyyc+fzzc