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Ln 2 - ln (3x + 2) =1

User Alessandra
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1 Answer

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When you add 2 logs together, you get the log of the product.
When you subtract 2 logs, you get the log of the quotient.

Like this:

Ln(2) - Ln(3x+2) is the Ln(2/3x+2) .

So now you have Ln(2/3x+2) = 1

Raise 'e' to the power of
each side of the equation: (2/3x+2) = e¹

Multiply each side by (3x+2): 2 = (e) (3x+2)

Divide each side by 'e': 2/e = 3x + 2

Subtract 2 from each side: (2/e) - 2 = 3x

Divide each side by 3: x = [ (2/e) - 2 ] / 3

= approx. -0.421... (rounded)

I checked this by writing it into the original equation in place of 'x'.
That took my about 5 tries, but it finally checked OK.

Please. DON't use my answer unless you understand
where it came from.
User Webeng
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7.4k points