Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
Solve logarithm equation?
log x^2 = (log x)^2
Instructions say to use any method, but I'm not sure what would be the best and easiest to learn/memorize.
3 Answers
- lenpol7Lv 77 years agoFavorite Answer
log x^2 = (log x)^2
2log x = log x logx
2 = log x logx / logx
Cancel down.
2 = log x
Antilog.
x = 10^2
x = 100
- GeronimoLv 77 years ago
Note: ( log(x) )² is normally written as: log ² (x)
log( x² ) = log ² (x) ... assuming base ten logs.
2 log(x) = log ² (x)
0 = log ² (x) – 2 log(x)
0 = log(x) • [ log(x) – 2 ]
log(x) = 0 and log(x) – 2 = 0
x = 1 ... log(x) = 2
... x = 10² = 100
So there are two solutions that are valid in the initial log equation
as shown below:
log( x² ) = log ² (x)
log( 1² ) = log ² (1) ... x = 1 solution
log( 1 ) = log ² (1)
0 = (0)² ... TRUE
log( x² ) = log ² (x)
log( 100² ) = log ² (100) ... x = 100 solution
log( 10000 ) = log ² (100)
4 = (2)² ... TRUE
- ?Lv 77 years ago
First, log x^2 = 2log x so now we have 2log x = (log x)^2 so to simplify the writing I'll write L for log x so we now have 2L = l^2 so L^2 - 2L = 0 giving l(L - 2) = 0 so L = 0 or L = 2 i.e. log x = 0 or log x = 2 and that gives us x= 1 or x = 100.
Source(s): Retired Maths Teacher