AQA FP1 2014 June — Question 2

Exam BoardAQA
ModuleFP1 (Further Pure Mathematics 1)
Year2014
SessionJune
TopicRoots of polynomials

2 The quadratic equation $$2 x ^ { 2 } + 8 x + 1 = 0$$ has roots \(\alpha\) and \(\beta\).
  1. Write down the value of \(\alpha + \beta\) and the value of \(\alpha \beta\).
    1. Find the value of \(\alpha ^ { 2 } + \beta ^ { 2 }\).
    2. Hence, or otherwise, show that \(\alpha ^ { 4 } + \beta ^ { 4 } = \frac { 449 } { 2 }\).
  2. Find a quadratic equation, with integer coefficients, which has roots $$2 \alpha ^ { 4 } + \frac { 1 } { \beta ^ { 2 } } \text { and } 2 \beta ^ { 4 } + \frac { 1 } { \alpha ^ { 2 } }$$
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