function z = BrCeq(C,lambda)
% C = BrCeq(lambda)
% Evaluates the equation for the integration
% constant C in the solution of the Bratu problem.
% Vectorized to make a 2-way table by outer products.
% 
C = C(:)'; 
lambda = lambda(:);
e = ones(size(lambda));
z = cosh(sqrt(lambda/8)*C) - e*C;