If α,β are the roots of x2+px+1=0, δ,γ the roots of x2+qx+1=0, then the value of (α−γ)(β−γ)(α+δ(β+δ)) is
q2 - p2
α+β=−p , αβ=1
Also γ2+1=−qγ and δ2+1=−qδ
(α−γ)(β−γ)(α+δ)(β+δ)=(αβ−(α+β)γ+γ2)(αβ+(α+β)δ+δ2)=(γ2+pγ+1)(δ2−pδ+1)=(pγ−qγ)(−pδ−qδ)=(q2−p2)γδ=(q2−p2)