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1. x2 = 3x - 1

A. 47
B. 47
C. 47
D. 47

Answer: Option A

Explanation:

x^{2} = 3 x - 1 \Rightarrow x^{2} + 1 = 3 x \Rightarrow (x^{2} + 1) = {(3 x)}^{2} \Rightarrow x^{4} + 2 x + 1 = 9 x^{2} \Rightarrow x^{4} + 1 = 7 x^{2} \Rightarrow {(x^{4} + 1)}^{2} = {(7 x^{2})}^{2} \Rightarrow x^{8} + 2 x^{4} + 1 = 49 x^{4} \Rightarrow x^{8} + 1 = 47 x^{4} \Rightarrow \frac{x^{8} + 1}{x^{4}} = 47

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