Practicing Success
If x - \(\frac{1}{x}\) = 8\(\sqrt{3}\) then find the value of x3 + \(\frac{1}{x^3}\) |
2744 2788 2702 2700 |
2702 |
⇒ If x - \(\frac{1}{x}\) = a then x + \(\frac{1}{x}\) = \(\sqrt {a^2 + 4}\) and If x + \(\frac{1}{x}\) = a then ⇒ x3 + \(\frac{1}{x^3}\) = a3 - 3a ATQ, x - \(\frac{1}{x}\) = 8\(\sqrt{3}\), then ⇒ x + \(\frac{1}{x}\) = \(\sqrt {(8\sqrt{3})^2 + 4}\) = 14 ⇒ x3 + \(\frac{1}{x^3}\) = 143 - 3 × 14 = 2702 |