Question
If x²- 5x + 1 = 0, what is the value of x² +
1/x2?Solution
x²- 5x + 1 = 0 ------- (i) Dividing eqn (i) by x => x²/x - 5x/x + 1/x = 0 => x + 1/x = 5 Now, x² + 1/x² = 5² - 2 = 23
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