(-9) 2 = 8 1,-9 2 =-8 1. Think of the minus sign as subtraction, and -9 as 0-9. If there are parentheses, first calculate the parentheses, then calculate the power, which is -9X(-9), and multiply the same symbol by positive; If there are no brackets, calculate the power first, that is, 9X9=8 1. If you calculate 0-8 1, you will naturally get -8 1.