allerySuppose x + 1/x = 5. Determine the value of x^2 + 1/x^2.
A23
B25
C27
D21
Answer & Solution
Correct answer: A. 23
Squaring both sides of x + 1/x = 5 gives x^2 + 1/x^2 + 2 = 25, so x^2 + 1/x^2 = 23.
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