To solve for x if log (x^2) - log 2x =
2.
Solution:
By property of
logarithms, log(a^m) = m * log a ,
log a = log b =
log (a/b).
So log x^2 - log2x = 2 = log 10^2, as log10^2 =
2log 10 = 2.
log (x^2 )/(2x) = log
10^2.
We take anti
logarithms:
x^2/(2x) =
100.
x^2 = 200x.
x^2-200x =
0.
x(x-200) = 0.
x = 0, or x=
200.
For x= 0, log(x) is undefined. So x= 200 is a valid
solution.
x =
200.
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