When U1 > 4, UN + 1 = 3un / 4 + 4 / UN, n →∞, UN → x, find X

When U1 > 4, UN + 1 = 3un / 4 + 4 / UN, n →∞, UN → x, find X

When n →∞, UN = UN + 1 = x, let n →∞ in UN + 1 = 3un / 4 + 4 / UN get x = X3 / 4 + 4 / x, so x ^ = 16. Because U1 > 4, every UN is a positive number, so the limit is also a positive number, x = 4