766. Вычисление логарифмов
- 1) log2 √2
Запишем √2 как 21/2. Тогда log2 21/2 = 1/2. - 2) log3 (1/∛3)
Запишем ∛3 как 31/3, тогда 1/∛3 = 3-1/3. log3 3-1/3 = -1/3. - 3) log0,5 (1/√32)
0,5 = 1/2 = 2-1. 32 = 25, √32 = 25/2, 1/√32 = 2-5/2.
log2-1 2-5/2 = –5/2 / –1 = 5/2. - 4) log7 (√7 / 49)
√7 = 71/2. 49 = 72.
√7 / 49 = 71/2 / 72 = 71/2 - 2 = 7-3/2.
log7 7-3/2 = -3/2. - 5) log128 64
128 = 27, 64 = 26.
log27 26 = 6/7. - 6) log27 243
27 = 33, 243 = 35.
log33 35 = 5/3. - 7) log64 256
64 = 43, 256 = 44.
log43 44 = 4/3. - 8) log81 27
81 = 34, 27 = 33.
log34 33 = 3/4. - 9) log√ (1/(3∛3))
√ = 31/2. 3∛3 = 3 * 31/3 = 34/3.
1/(3∛3) = 3-4/3.
log31/2 3-4/3 = –4/3 / (1/2) = -8/3. - 10) log1/2 (1/(4√2))
1/2 = 2-1. 4√2 = 22 * 21/2 = 25/2.
1/(4√2) = 2-5/2.
log2-1 2-5/2 = –5/2 / –1 = 5/2.