Question

Sabendo que log 2 = 0,301 e log 3 = 0,477, qual o valor de log (0,12)?

Answer 1

$\log(0.12)=\\\\\log\left(\dfrac{12}{100}\right)=\\\\\log(12)-\log(100)=\\\\\log(3\cdot4)-2=\\\\\log(3)+\log(4)-2=\\\\0.477+\log(2^2)-2=\\\\0.477-2+2\log(2)=\\\\0.477-2+2(0.301)=0.477+0.602-2=1.079-2=-0.921$