SOLUTION: How do you solve: lnx^2 = (lnx)^2 - 15 (solve for x)
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Question 546424
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How do you solve:
lnx^2 = (lnx)^2 - 15 (solve for x)
Answer by
Alan3354(69443)
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lnx^2 = (lnx)^2 - 15 (solve for x)
ln(x^2) = 2ln(x)
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2ln(x) = (ln(x))^2 - 15
Sub y for ln(x)
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2y = y^2 - 15
y^2 - 2y - 15 = 0
(y-5)*(y+3) = 0
y = -3,5
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ln(x) = -3
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