9. Usando log 3 = 0, 4771, calcule: a) log 3000 b) log 0, 003 c) log 0, 81 a) b) c) a) 3,4771 b) -2,5229 c) -0,0915

As respostas estão corretas: a) log 3000 = log (3 x 1000) = log 3 + log 1000 = log 3 + 3 = 3,4771 + 3 = 6,4771 b) log 0,003 = log (3 x 10^-3) = log 3 + log 10^-3 = log 3 - 3 = 0,4771 - 3 = -2,5229 c) log 0,81 = log (9/10)^2 = 2 log (3/10) = 2 (log 3 - log 10) = 2 (0,4771 - 1) = 2 (-0,5229) = -1,0458 Portanto, as respostas são: a) 3,4771 b) -2,5229 c) -1,0458