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21. If α, β are the roots of the equation x2-px+q= 0, then find the quadratic equation the roots of which are α2-β2 α3-β3 and α3β2+α2β3.

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Dear student
Given: α and β are roots of x2-px+q=0α+β=-coeff. of xcoeff. of x2=--p1=pαβ=constant termcoeff. of x2=q1=qWe know that α+β2=α2+β2+2αβα2+β2=p2-2qand α-β2=α2+β2-2αβ=p2-2q-2q=p2-4qSo, α-β=±p2-4qWe want to find the quadratic equation whose roots are:α2-β2α3-β3 and α3β2+α2β3let S and P be the sum and product of roots respectively.S=α2-β2+α3-β3+α3β2+α2β3S=α+βα-β+α-βα2+β2+αβ+α2β2α+βCase I when α-β=p2-4qS=p×p2-4q+p2-4qp2-2q+q+q2p=pp2-4q+p2-4qp2-2q+q+q2p=p2-4qp+p2-q+pq2and P=α2-β2α3-β3 α2β2α+β=α+βα-βα-βα2+β2+αβα2β2α+β=pp2-4qp2-qq2p=p2q2p2-4qp2-qSo, required polynomial is=x2-Sx+P=x2-p2-4qp+p2-q+pq2x+p2q2p2-4qp2-qSimilarly try when α-β=-p2-4q
Regards

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