Target Mathematics

1.40: Relationships between roots

4PM1/1/January/2018 — Question 9 · 13 marks

It is given that α\alpha and β\beta are such that α+β=52\alpha+\beta=-\dfrac52 and αβ=5\alpha\beta=-5.
(a) Form a quadratic equation with integer coefficients that has roots α\alpha and β\beta. (2)
Without solving the equation found in part (a)
(b) find the value of
(i) α2+β2\alpha^2+\beta^2
(ii) α3+β3\alpha^3+\beta^3 (5)
(c) Hence form a quadratic equation with integer coefficients that has roots
(α1α2)and(β1β2)\left(\alpha-\dfrac1{\alpha^2}\right)\quad\text{and}\quad\left(\beta-\dfrac1{\beta^2}\right)
(6)