The document discusses powers of negative numbers. Some key points are: 1) The even powers of -2 are equal to the same power of 2, while the odd powers of -2 are the negative of the same power of 2. 2) The powers of -1 follow a pattern of (-1)1 = -1, (-1)2 = 1, (-1)3 = -1, and so on. 3) To write fractions like 42/45, we define negative powers using a new meaning - that x(-n) = 1/xn, to allow expressions like 4(-3) to have meaning as 1/43.