Question

Se log2=0,30,log3=0,47,log5=0,69 e log7=0,84,calcule:

a) log20

b)log30

c)log28

d)log140

Answer 1

Se log2=0,30,log3=0,47,log5=0,69 e log7=0,84,calcule:

a) log20
log (2.10) = log 2 + log 10 -> 0,30 + 1 = 1,30

b) log 30
log(3.10) = log 3 + log 10 -> 0,47 + 1 = 1,47

c)log28
log (2.7.2) = log2 + log7+ log2 -> 0,30 + 0,84 + 0,30 = 1,44

d)log140
log(7.10.2) = log7 + log 10 + log 2 ->  0,84 + 1 + 0,30  = 2,14

Answer 2

a) log20 = log (2.10) = log 2 + log 10 -> 0,30 + 1 = 1,30

b) log 30 = log(3.10) = log 3 + log 10 -> 0,47 + 1 = 1,47

c)log28 = log (2^2 .7.) = 2.log2 + log7-> 0,30 + 0,84 + 0,30 = 1,44

d)log140 = log(7.10.2) = log7 + log 10 + log 2 ->  0,84 + 1 + 0,30  = 2,14