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If $$x = 3 + 2 \sqrt 2 $$, then the value of $$x^2 + \frac{1}{x^2}$$ is
Given, $$x=3+2\sqrt{2}$$
$$\Rightarrow$$ $$\frac{1}{x}=\frac{1}{3+2\sqrt{2}}\times\frac{3-2\sqrt{2}}{3-2\sqrt{2}}$$
$$\Rightarrow$$ $$\frac{1}{x}=\frac{3-2\sqrt{2}}{9-8}$$
$$\Rightarrow$$ $$\frac{1}{x}=3-2\sqrt{2}$$
$$\left(x+\frac{1}{x}\right)^2=\left(3+2\sqrt{2}+3-2\sqrt{2}\right)^2$$
$$\Rightarrow$$ $$x^2+\frac{1}{x^2}+2=6^2$$
$$\Rightarrow$$ $$x^2+\frac{1}{x^2}+2=36$$
$$\Rightarrow$$ $$x^2+\frac{1}{x^2}=34$$
Hence, the correct answer is Option D
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