If $$x=8-\sqrt{32}$$ and $$y=2+\sqrt{2}$$, then $$\left(x+\frac{1}{y}\right)^2$$ is given by:
$$x=8-\sqrt{32}$$ and $$y=2+\sqrt{2}$$,
We have to find the value of $$\left(x+\frac{1}{y}\right)^2$$
$$\left(8-\sqrt{\ 32}+\ \frac{\ 1}{2+\sqrt{\ 2}}\right)^2$$
$$(\ \frac{\ 8\left(2+\sqrt{\ 2}\right)-\sqrt{\ 32}\left(2+\sqrt{\ 2}\right)+\ \ 1}{2+\sqrt{\ 2}})^2$$
$$\left(\ \frac{\ 9}{2+\sqrt{\ 2}}\right)^2$$
$$\ \frac{\ 81}{6+2\sqrt{\ 2}}$$
$$\left(\ \frac{\ 1}{y}\right)^2=\ \left(\frac{\ 1}{2+\sqrt{\ 2}}\right)^2$$ = $$6+2\sqrt{\ 2}$$
=$$\left(\ \frac{\ 2-\sqrt{\ 2}}{2}\right)^{^2}$$
=$$\ \frac{\ 6-4\sqrt{2\ }}{4}$$
=$$\ \frac{\ 3-2\sqrt{2\ }}{2}$$
$$x^2=64+32-64\sqrt{\ 2}$$
=$$96-64\sqrt{\ 2}$$
=32($$3-2\sqrt{\ 2}$$) = 32*$$2y^2$$
we get, $$x^{2\ }=\ 64y^2$$
$$\ \frac{\ 81}{y^2}=\ \frac{\ 81}{64}x^2$$
D is the correct answer.
Alternative solution,
$$xy=\left(8-\sqrt{\ 32}\right)\left(2+\sqrt{\ 2}\right)=4\sqrt{\ 2}\left(\sqrt{\ 2}-1\right)\times\ \sqrt{\ 2}\left(\sqrt{\ 2}+1\right)=8\left(2-1\right)=8$$
(As $$xy=8\ \longrightarrow\ y=\dfrac{x}{8}$$)
$$\left(x+\frac{1}{y}\right)^2=\left(\frac{\left(xy+1\right)}{y}\right)^2=\left(\frac{\left(xy+1\right)\times\ x}{8}\right)^2=\left(\frac{\left(8+1\right)\times\ x}{8}\right)^2=\frac{81}{64}\times\ x^2$$
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