Michael J. answered 03/30/16
Tutor
5
(5)
Effective High School STEM Tutor & CUNY Math Peer Leader
Alan gave you approximations. In case you need exact solutions (radical form), as sometimes they require, go with these.
0.30 = log(x)
We know that the solution to a log is the exponent to the base number 10.
100.30 = x
Rewrite the exponent as a fraction.
10(3/10) = x
Write the left side as a radical.
10√(103) = x
10√(1000) = x
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0.30 = ln(y)
The solution to a natural log is the exponent of base number e.
e0.30 = y
Putting the exponent in fraction form,
e(3/10) = y
Then in radical form,
10√(e3) = y
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For the next one, we try to use the properties of logs.
log(1.3) =
log(1 3/10) =
log(13 / 10) =
Use the difference of logs properties.
log(13) - log(10) =
log(13) - 1