Eigenvalues of symmetric complex matrices .

Is it true that for symmetric matrix with complex entries all eigenvalues are real.

I have seen the proof for Hermitian matrices and proved it for real symmetric matrices,but for complex symmetric matrices I dont know how to determine this.

Thank you in advance for your help.

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Hint: Try a 2x2 matrix where all entries = $i$. –  Amzoti Mar 5 '13 at 5:09
This is true for self-adjoint matrices, aka hermitian matrices. Not for symmetric matrices. Look at $\left(\matrix{0&i\\i&0}\right)$ for instance. –  julien Mar 5 '13 at 5:10
@julien: easier example than mine! Regards –  Amzoti Mar 5 '13 at 5:12
How about $\begin{bmatrix} i \end{bmatrix}$. No simpler than that! –  copper.hat Mar 5 '13 at 5:54
@copper.hat: Nice example! –  Amzoti Mar 5 '13 at 6:06
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1 Answer

The question has been answered in the comments; this is a community wiki answer to allow the question to be marked as answered.

The answer is no; symmetric matrices with complex entries do not in general have real eigenvalues.

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