Values from x plus its reciprocal

Values from x plus its reciprocal

IP 2
8 marks

It is given that \(x+\dfrac{1}{x}=5\), where \(x\ne0\).

  1. Find the value of \(x^2+\dfrac{1}{x^2}\).[2]
  2. Find the value of \(\left(x-\dfrac{1}{x}\right)^2\).[2]
  3. Show that \(x^4+\dfrac{1}{x^4}=527\).[2]
  4. Explain why there is no real number \(x\) for which \(x+\dfrac{1}{x}=1\).[2]

Solution:

Solution locked

680+ questions here come with free worked solutions. A free account saves your questions and progress; this one needs tuition enrolment.

Create a free account to practise similar questions.

Answer:(a) \(23\) (b) \(21\) (c) Shown (d) It would give \(\left(x-\dfrac{1}{x}\right)^2=-3<0\)

Need help? Join our IP Math tuition programme.

Learn more