SOLUTION: I need help with a natural log equation: 4ln x - ln 2 = ln 128 (I know the answer is 4, can you show me the steps) Thanks

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Question 71142: I need help with a natural log equation:
4ln x - ln 2 = ln 128 (I know the answer is 4, can you show me the steps)
Thanks

Found 2 solutions by Earlsdon, stanbon:
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x:
4ln%28x%29-ln%282%29+=+ln%28128%29 Apply the power rule n%2Aln%28x%29+=+ln%28x%5En%29 to the first term:
ln%28x%5E4%29-ln%282%29+=+ln%28128%29 Now apply the quotient rule for logarithms to the left side.
ln%28x%5E4%2F2%29+=+ln%28128%29 Remembering that IfM+=+Nthenln%28M%29+=+ln%28N%29, you can write:
%28x%5E4%29%2F2+=+128 Multiply both sides by 2.
x%5E4+=+256 Take the 4th root of both sides.
x+=+4

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
4ln x - ln 2 = ln 128
lnx^4 - ln2 = ln128
ln(x^4/2) = ln128
x^4/2 = 128
x^4 = 256
x = 4
Cheers,
Stan H.