Question

Usando apenas que log2= 030,log3= 0,47e log5= 0,69,calcule.
a) log 0,5
b) log 3/2
c) log 20
d) log 20 + log 40 + log 1600
e) log 30
f) log 32

Answer 1

a)  log 0,5 = log 5/10 = log 5 - log10 =  0,69 - 1 = -0,31
b) log3/2 = log3 - log2 = 0,47 - 0,30 = 0,17
c) log20 = log(4.5)=log(2²) + log5 = 2×0,30 + 0,69 = 0,60+0,69 = 1,29
d) log20 = 1,29
    log40 =log(2³×5)=log2³ + log5 = 3×0,30 + 0,69 =0,90 + 0,69 = 1,59
    log1600 = log2^4 + log100 = 4×0,30 + 2 = 1,2 + 2 = 3,2
    1,29+ 1,59 + 3,2 = 6,08
e) log30 = log3 + log10 = 0,47 + 1 = 1,47
f)  log32 = log 2^5  = 5×0,30 = 1,5