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If $A$ is a $2\times 2$ real matrix that has (non-real) eigenvalues $\lambda_1$ and $\lambda_2$ when viewed as a complex matrix, then what can we conclude?

$\lambda_1+\lambda_2=0$

$\lambda_1\lambda_2$ is a positive real number

$\lambda_1\lambda_2$ is a negative real number

$\lambda_1=\lambda_2$