How do you use log to verify that 10 = 5 * 2 ?

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Answer 1 · 2018-06-25T11:51:36

Given #10=5·2# we take log in both sides. Then we have

#log10=log(5·2)=log5+log2# by log rules

#log10=1# because allways #log_b b=1#

Now use a calculator to find #log5# and #log2#

#log5=0.6989700043#
#log2=0.30102999957#

The sum of both numbers have to be 1. Lets check

#0.6989700043+0.30102999957=1#