Question

Oblicz:

a) log4- log5 -log125
b) log₇14 - log₇2V7
c) log₅0,5 + 2x log₅20 -3x log₅2
d) log₅9 +2x (log₅1-log₅3)
e)log₂₇9 +log₂₇243 +log₂₇3⁸
f) log2 + log½ +log3⅓ +log3

Answer 1

A) log4- log5 -log125
log(4/5/125)=log 0,032

b) log₇14 - log₇2V7
log₇14-log₇128=-log₇14/128=log₇7/64=1/log₇64

c) log₅0,5 + 2log₅20 -3log₅2
log₅0,5+log₅400-log₅8 = log₅(0,5*400)/8=log₅200/8=log₅25=2

d) log₅9 +2(log₅1-log₅3)
log₅9+log₅1-log₅9=0

e)log₂₇9 +log₂₇243 +log₂₇3⁸
log₂₇9+log₂₇243+log₂₇6561=log₂₇14348907=5

f) log2 + log½ +log3⅓ +log3 = log10=1