The set of all values of $\lambda$ for which the equation ${\cos ^2}2x - 2{\sin ^4}x - 2{\cos ^2}x = \lambda $ has a real solution $x$, is :

Question

$\left[ { - 2, - 1} \right]$

$\left[ { - {3 \over 2}, - 1} \right]$

$\left[ { - 2, - {3 \over 2}} \right]$

$\left[ { - 1, - {1 \over 2}} \right]$

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