Question

The characteristic curves for an elliptic system are ___________

(a) real and imaginary

(b) both real

(c) both imaginary

(d) both zeros

This question was addressed to me in an interview for job.

This interesting question is from Mathematical Behaviour of PDE topic in division Mathematical Behaviour of Partial Differential Equations of Computational Fluid Dynamics

Answer 1

The correct option is (c) both imaginary

Explanation: Elliptic equations have their determinant less than zero and the roots of this determinant are both imaginary. So, the curves are also imaginary.