If x + 1/x = 3, find x² + 1/x².
A11
B9
C8
D7
Answer & Solution
Correct answer: D. 7
1. Square both sides: (x + 1/x)² = x² + 2 + 1/x² = 9.
2. x² + 1/x² = 9 − 2 = 7.
_Source: TSICET 2024 PYQ Q.91 (Shift 1, Algebra)_
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