If x + \(\frac{1}{x}\) = 4 Find x5 + \(\frac{1}{x^5}\) |
736 776 702 724 |
724 |
Formula → [x5 + \(\frac{1}{x^5}\) = (x3 + \(\frac{1}{x^3}\)) (x2 + \(\frac{1}{x^2}\)) - (x + \(\frac{1}{x}\))] → [x2 + \(\frac{1}{x^2}\) = a2 - 2 If x + \(\frac{1}{x}\) = a] → [x3 + \(\frac{1}{x^3}\) = a3 - 3a] x + \(\frac{1}{x}\) = 4 x2 + \(\frac{1}{x^2}\) = 42 - 2 = 14 x3 + \(\frac{1}{x^3}\) = (4)3 - 3 × 4 = 52 Now; x5 + \(\frac{1}{x^5}\) = 52 × 14 - 4 = 724 |