If ${ a }_{ i }$ is positive or negative as $i$ even or odd respectively.
If ${ x }^{ 4 }+{ { a }_{ 1 } }{ x }^{ 3 }+{ a }_{ 2 }{ x }^{ 2 }+{ a }_{ 3 }x+5=0\quad$
has four Positive roots the them find minimum value of ${ a }_{ 1 }{ a }_{ 3 }$

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