因为 x + 1/x = a + 1/a的解为 x = a 或 x = 1/a
所以 x + 1/(x-3) = (x - 3) + 1/(x-3) = 8又1/5－3＝41/5 - 3 = 26/5 = 5 + 1/5
因此有 x - 3 = 5或 x - 3 = 1/5
解得 x = 8 或 x = 3又1/5