Question

Which of these is a sufficient condition for a discretized equation?

(a) Neither the opposite sign rule nor the zero sum rule

(b) Both the opposite sign and the zero sum rules

(c) The opposite signs rule

(d) The zero sum rule

I got this question during an interview.

Origin of the question is Diffusion Problem topic in section Diffusion Problem of Computational Fluid Dynamics

Answer 1

The correct choice is (c) The opposite signs rule

Best explanation: For of the discretized equations to be bounded, the sufficient condition is the opposite signs rule. Sufficient condition means that the rule will be enough to make sure that the equation is bounded.