SOLUTION: ln x^-3 - (ln x)^2 = -28

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Question 684903: ln x^-3 - (ln x)^2 = -28
Found 2 solutions by Alan3354, MathTherapy:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
ln x^-3 - (ln x)^2 = -28
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If you mean ln(x^-3) and (ln(x))^2
-3ln(x) - (ln x)^2 = -28
(ln(x))^2 + 3ln(x) - 28 = 0
sub u for ln(x)
u%5E2+%2B+3u+-+28+=+0
(u + 7)*(u - 4) = 0
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ln(x) = -7
x+=+e%5E%28-7%29
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ln(x) = 4
x+=+e%5E4

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

ln x^-3 - (ln x)^2 = -28

x+=+%281%2Fe%5E-28%29%5E%281%2F5%29

highlight_green%28x+=+270.4264%29

You can do the check!!

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