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If $$x^4+\frac{1}{x^4}=14159$$, then the value of $$x+\frac{1}{x}$$ is:
Given, $$x^4+\frac{1}{x^4}=14159$$
$$\Rightarrow$$ $$x^4+\frac{1}{x^4}+2=14159+2$$
$$\Rightarrow$$ $$\left(x^2+\frac{1}{x^2}\right)^2=14161$$
$$\Rightarrow$$ $$\left(x^2+\frac{1}{x^2}\right)^2=\left(119\right)^2$$
$$\Rightarrow$$ $$x^2+\frac{1}{x^2}=119$$
$$\Rightarrow$$ $$x^2+\frac{1}{x^2}+2=119+2$$
$$\Rightarrow$$ $$\left(x+\frac{1}{x}\right)^2=121$$
$$\Rightarrow$$ $$x+\frac{1}{x}=11$$
Hence, the correct answer is Option A
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