If $$a^{4} + \frac{1}{a^{4}} = 50$$, then find the value of $$a^{3} + \frac{1}{a^{3}}$$
$$a^{4} + \frac{1}{a^{4}} = 50$$
$$a^{4} + \frac{1}{a^{4}} + 2= 50 + 2$$
$$(a^2+\frac{1}{a^2})^2=52$$
$$(a^2+\frac{1}{a^2})=\sqrt{52}$$
$$a^2+\frac{1}{a^2} + 2Â = \sqrt{52} + 2$$
$$(a + \frac{1}{a})^2 =Â \sqrt{52} + 2$$
$$(a + \frac{1}{a})Â = \sqrt{\sqrt{52} + 2}$$
$$a^{3} + \frac{1}{a^{3}} = (a + b)^3 + 3ab(a + b)$$
=$$(\sqrt{\sqrt{52} + 2})^3 +Â \sqrt{\sqrt{52} + 2}$$
=$$(\sqrt{2\sqrt{13} + 2})^3 + \sqrt{2\sqrt{13} + 2}$$
=$$\sqrt{2\sqrt{13} + 2}(1 +Â (\sqrt{2\sqrt{13} + 2})^2)$$
=$$\sqrt{2\sqrt{13} + 2}(1 + {2\sqrt{13} + 2})$$
=$$\sqrt{2(\sqrt{13} + 1})(3 + {2\sqrt{13}})$$
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