Log4 64+log5 25+log9 81
log4 64+log5 25+log9 81 = log4 4^3+log5 5^2+ log9 9^2 =
= 3 log4 4+ 2 log5 5+ 2 log9 9 = 3 *1 + 2 *1 + 2 *1 = 7