SOLUTION: How do you solve for x? (exact values) ln(x)+ln(x-4)=4

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Question 787136: How do you solve for x? (exact values)
ln(x)+ln(x-4)=4
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Use: "The sum of the logs is the log of the product"



Use the definition of the logarithm function:

to write:



Put the quadratic in standard form:



Use the quadratic formula and simplify (Hints: is simply a constant, and the only meaningful way to represent that particular constant exactly. Also, 4 factors out of the radicand)

John

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