SOLUTION: solve lnx +ln(x+3)=1

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Question 136379: solve lnx +ln(x+3)=1
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
lnx+%2Bln%28x+%2B+3%29+=+1
ln%28x%2A%28x+%2B+3%29%29+=+1
Let y+=+x%2A%28x%2B3%29
Rewrite equation as
ln%28y%29+=+1
Rewite this as
e%5E1+=+y
or
e+=+x%2A%28x+%2B+3%29
x%5E2+%2B+3x+=+e
Complete the square
x%5E2+%2B+3x+%2B+%283%2F2%29%5E2+=+e+%2B+%283%2F2%29%5E2
%28x+%2B+%283%2F2%29%29%5E2+=+e+%2B+9%2F4
take square root of both sides
x+%2B+%283%2F2%29+=+0+%2B-sqrt%28e+%2B+9%2F4%29
x+=+-%283%2F2%29+%2B-sqrt%28e+%2B+9%2F4%29 answer
(unless I goofed)