Question

How the type of PDE is identified using Cramer’s rule?

(a) By equating the Cramer’s denominator to 1

(b) By equating the Cramer’s numerator to 1

(c) By equating the Cramer’s denominator to 0

(d) By equating the Cramer’s numerator to 0

I had been asked this question during an interview for a job.

This intriguing question comes from Classification of PDE topic in portion Mathematical Behaviour of Partial Differential Equations of Computational Fluid Dynamics

Answer 1

Right choice is (c) By equating the Cramer’s denominator to 0

Best explanation: The denominator of Cramer’s solution is equated to zero to find the type of PDE. The denominator is equated to zero to make the solution indeterminate.