If x+\(\frac{1}{x}\) = 3, then x5+\(\frac{1}{{x}^{5}}\) equals to:

121 126 123 129

123

x+\(\frac{1}{x}\) = 3, x2+\(\frac{1}{{x}^{2}}\) = 7 and x3+\(\frac{1}{{x}^{3}}\) = 18 Now, x5+\(\frac{1}{{x}^{5}}\) = (x2+\(\frac{1}{{x}^{2}}\)) (x3+\(\frac{1}{{x}^{3}}\)) - (x+\(\frac{1}{x}\))                                          = (7) (18) - 3 = 126 - 3 = 123