SOLUTION: I need help solving this logarithm log(2x)+3log(x^2)=72 All the other ones I have done are equal to something small.

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Question 378678: I need help solving this logarithm log(2x)+3log(x^2)=72
All the other ones I have done are equal to something small.
Found 2 solutions by richard1234, stanbon:
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
By basic properties of logarithms,
log (2x) = log 2 + log x
log (x^2) = 2 log x
This equation becomes
log 2 + log x + 6 log x = 72
7 log x = 72 - log 2
log x = (72 - log 2)/7
x+=+10%5E%28%2872+-+log+2%29%2F7%29 (assuming the base is 10)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
log(2x)+3log(x^2) = 72
----
log(2x) + log(x^2)^3 = 72
-----
log(2x) + log(x^6) = 72
----
log[2x*x^6] = 72
---
log[2x^7] = 72
-----
2x^7 = 10^72
-----
x^7 = 5*10^71
---
x = 1.7487*10^10
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Cheers,
Stan H.