1) log₉15 + log₉18 – log₉10 = log₉15 * 18/10 = log₉ + 3 * 4 = log₉12

2) 2log_1/56 – 1/2log_1/5400 – 4log_1/54<45 = log_1/536 * 4/20 * 455 = log_1/51/5² = 2^1/5

3)ա) log₅ * (7 + 2<6) + log₅ * (7 – 2<6) = log₅ * (7 + 2 – <6) * (7 – 2 – <6) = log₅ * (19 * -4 * 6) = log₅ * (49 – 24) = log₂25 = 2