SOLUTION: hello i need help on this LN problem ln^x+ln^3x=12

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Question 108918This question is from textbook
: hello i need help on this LN problem
ln^x+ln^3x=12 This question is from textbook

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Is this the problem?
ln%28x%29%2Bln%283x%29=12
From the log rules,
ln%28a%29%2Bln%28b%29=ln%28ab%29
Then
ln%28x%29%2Bln%283x%29=12
ln%283x%5E2%29=12
3x%5E2=e%5E12
x%5E2=e%5E12%2F3
x=sqrt%28e%5E12%2F3%29 and x=-sqrt%28e%5E12%2F3%29
x=232.92 and x=-232.92
Check your answers.
ln%28x%29%2Bln%283x%29=12
ln%28232.92%29%2Bln%28698.76%29=12
5.45%2B6.55=12
12=12
True statement.
Good answer.