Log₅(18 -x) = log₃9
log₅(18 - x) = 2
18 - x = 5²
18 -x = 25
x = 18 - 25
x = - 7
Проверка
log₅ (18 - (-7)) = log₃9
log₅25 = 2
2 = 2
Ответ: х = - 7
2.
=
= х³/3 |₁² + 2/3*√x |₁² = 2³/3 - 1³/3 + 2/3(√2³ - √1³) =
= 8/3 - 1/3 + 2/3 * (√8 - 1) = 7/3 + 2/3 * (2√2 - 1)