Question

Dados os log 2= 0,30 e log 5= 0,70, determine:

a)log 20

b)log 0,0002

c)log 250

Answer 1

Temos que log(ab) = log(a) + log(b)

a) log(20) = log(2*10) = log(2) + log(10) = 0,3 + 1 = 1.3

b) log(0.0002) = log(2*10^-4) = log(2) + log(10^-4) = 0.3 - 4 = -3.7

c) log(250) = log(5*^2*10) = 2log(5) + log(10) = 1.4 + 1 = 2.7

Answer 2

Bom dia Ayla

log(2) = 0.30
log(5) = 0.70

a)

log(20) = log(4*5) = log(2)  + log(2) + log(5)
log(20) = 0.30 + 0.30 + 0.70 = 1.30 

b)

log(0.0002) = log(2/10000) = log(2) - log(10000) = 0.30 - 4 = -3.70 

c)

log(250) = log(500/2) = log(500) - log(2)

log(500) - log(2) = log(5) + log(100) - log(2) 
log(5) + log(100) - log(2) = 0.70 + 2 - 0.30 = 2.40