N2009 P1 Q1

N2009 P1 Q1

6 marks
Past Year National Exams
Free
  1. The first three terms of a sequence are given by \({{u}_{1}}=10\), \({{u}_{2}}=6\), \({{u}_{3}}=5\). Given that \({{u}_{n}}\) is a quadratic polynomial in \(n\), find \({{u}_{n}}\) in terms of \(n\).[4]
  2. Find the set of values of \(n\) for which \({{u}_{n}}\) is greater than \(100\).[2]

Video Solution:

Default solution

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Answer:(i) \(u_n = \dfrac{3}{2}n^2 - \dfrac{17}{2}n + 17\) (ii) \(\{n \in \mathbb{Z}^+ : n \geq 11\}\)

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