If $x^4 + \frac{1}{x^4}=14159$, Then a Possible value of $ x + \frac{1}{x}$is :
Answer & explanation
Correct answer: option 4
If x4 + \(\frac{1}{x^4}\) = a
then x2 + \(\frac{1}{x^2}\) = \(\sqrt {a + 2}\) = b
and x + \(\frac{1}{x}\) = \(\sqrt {b + 2}\)
If $x^4 + \frac{1}{x^4}=14159$
then x2 + \(\frac{1}{x^2}\) = \(\sqrt {14159 + 2}\) = 119
and x + \(\frac{1}{x}\) = \(\sqrt {119 + 2}\) = 11