Log915+ log918- log910
Log9 (15) + log9(18) - log9(10) = = log9 (15*18) - log9(10) = = log9 (270) - log9(10) = = log9 (270/10) = = log9 (27) = = log3^2(3^3) = = 1/2*log3(3^3) = = 1/2*3 = 1,5