If $x = 3 + 2\sqrt{2}$, then the value of $x^2 + \frac{1}{x^2}$ is :
Answer & explanation
Correct answer: option 4
If $x = 3 + 2\sqrt{2}$,
then the value of $x^2 + \frac{1}{x^2}$ is = ?
If $x = 3 + 2\sqrt{2}$
x2 = 9 + 8 + $12\sqrt{2}$ = 17 + $12\sqrt{2}$
and \(\frac{1}{x^2}\) = 17 - $12\sqrt{2}$
Now, $x^2 + \frac{1}{x^2}$ = 17 + $12\sqrt{2}$ + 17 - $12\sqrt{2}$ = 34