# Its part 2...

Algebra Level 5

Given that $$x^4+(1-2k)x^2+k^2-1=0$$, where $$k$$ is real, has no real roots when $$x^2$$ is imaginary or $$x^2<0$$ and has real roots when $$x^2\ge 0$$.

Find the range of $$k$$, when the equation has four real roots.

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