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Question
If `x + 1/x = 3`, find the value of `x^2 + 1/x^2`.
Sum
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Solution
Given: `x + 1/x = 3`
Step-wise calculation:
Square both sides:
`(x + 1/x)^2 = 3^2` which expands to `x^2 + 2 + 1/x^2 = 9`
Rearranging gives:
`x^2 + 1/x^2 = 9 - 2`
`x^2 + 1/x^2 = 7`
So, the value of `x^2 + 1/x^2` is 7.
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Chapter 3: Expansions - Exercise 3B [Page 71]
