Найдите значение выражения:
а) 125-1 ⋅ 252
б) 0,0001 ⋅ (103)2 ⋅ (0,1)-2
в) 16-3 ⋅ 45 / 8
г) 94 ⋅ (1/27)-3 ⋅ 81-4
Решение:
а) 125-1 ⋅ 252 = (53 )-1 ⋅ (52 )2 = 53 ⋅(-1) ⋅ 5 2⋅2 = 5-3 ⋅ 54 = 5-3+4 = 5
б) 0,0001 ⋅ (103)2 ⋅ (0,1)-2 = 1/104 ⋅ 103⋅2 ⋅ (1/10)-2 = 10-4 ⋅ 106 ⋅ 102 = 10-4+6+2 = 104 = 10000
в) 16-3 ⋅ 45 / 8 = (24)-3 ⋅ (22)5 = 24⋅(-3) ⋅ 2 2⋅5 / 23 = 2-12 ⋅ 210 / 23 = 2-12+10 / 23 = 2-2/23 = 2-2-3 = 2-5 = 1/25 = 1/32
г) 94 ⋅ (1/27)-3 ⋅ 81-4 = (32)4 ⋅ (3-3) ⋅ (34)-4 = 32⋅4 ⋅ 3-3⋅(-3) ⋅ 34⋅(-4) = 38 ⋅ 39 ⋅ 3-16 = 38+9-16 = 31 = 3
Источник : Учебник по Алгебре 9 класса авторов Ю.Н. Макарычев, Н.Г. Миндюк, К.И. Нешков, С.Б. Суворова, 2014г.