Sum of powers of roots

A question is this type if and only if it asks to find the value of expressions like α^n + β^n + γ^n using relationships between roots and coefficients.

27 questions · Standard +0.8

4.05a Roots and coefficients: symmetric functions
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Pre-U Pre-U 9795/1 2013 November Q10
8 marks Standard +0.8
The roots of the equation \(x^4 - 2x^3 + 2x^2 + x - 3 = 0\) are \(\alpha\), \(\beta\), \(\gamma\) and \(\delta\). Determine the values of
  1. \(\alpha^2 + \beta^2 + \gamma^2 + \delta^2\), [2]
  2. \(\frac{1}{\alpha} + \frac{1}{\beta} + \frac{1}{\gamma} + \frac{1}{\delta}\), [2]
  3. \(\alpha^3 + \beta^3 + \gamma^3 + \delta^3\). [4]
Pre-U Pre-U 9795 Specimen Q7
8 marks Challenging +1.2
The equation $$8x^3 + 12x^2 + 4x - 1 = 0$$ has roots \(\alpha, \beta, \gamma\). Show that the equation with roots \(2\alpha + 1, 2\beta + 1, 2\gamma + 1\) is $$y^3 - y - 1 = 0.$$ [3] The sum \((2\alpha + 1)^n + (2\beta + 1)^n + (2\gamma + 1)^n\) is denoted by \(S_n\). Find the values of \(S_3\) and \(S_{-2}\). [5]