Jawabanmu

2014-09-01T19:13:24+07:00
log 18
= log 2 + log 3²
= log 2 + 2 log 3
= 0,3010 + 2. 0,4711
= 03010 + 0,9542
= 1,2552
log 21
= log 7 + log 3
= 0,8451 + 0,4771
=1,3222
log 10,5
= log 105/10
= log 105 - log 10
= (log 21 + log 5) - 1
= 1,3222+ log 5 - 1
= 0,3222 + log 5
log 1/7
= log 1 - log 7
= 0 - 0,8451
= - 0,8451
1 5 1