Express r in terms of p and q if the roots of the equation x2+px+q=0 are α,β and the roots of the equation x2−rx+s=0 are α4,β4
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p - 2q - 2q
2q - p - 2q
α+β = -p, αβ = q α4+β4 = r = (α2+β2)2 - 2α2β2 = ((α+β)2−2αβ)2−2α2β2 r = (p2−2q)2−2q2