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If a and b are the roots of the equation $$2x^2-px+7=0$$ Then a-b is a root of ?

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1 Answer 1

up vote 5 down vote accepted

So, $a+b=\frac{p}{2}$ and $ab=\frac{7}{2}$

If $y=a-b=>y^2=(a+b)^2-4ab$

$=>y^2=(\frac{p}{2})^2-4 \frac{7}{2}$

So, a-b is a root of $4y^2-p^2+56=0$

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