№ 9: (1) log₂ 12 + log₂ 5 − log₂ 15; (2) log₁₅ ⁵√225; (3) 3^(1 + log₃ 2); (4) log₉ 1; (5) log₁₃ 13.

1) log₂(12 × 5 ÷ 15) = log₂ 4 = 2.

2) ⁵√225 = 15^(2/5), поэтому log₁₅ ⁵√225 = 2/5.

3) 3^(1 + log₃ 2) = 3 × 2 = 6.

4) log₉ 1 = 0.

5) log₁₃ 13 = 1.