If a + 1/a = 4, then what is the value of a^4 + 1/(a^4)?

If $K+\frac{1}{K}=n$

then, $K^2+\frac{1}{K^2}$ = n² – 2

If $ a + \frac{1}{a} = 4$

$ a^2 + \frac{1}{a^2} = 4^2 - 2 = 14$

$a^4 + \frac{1}{a^4}$ = 14^2 - 2 = 194