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# Natural log, find x watch

1. Attachment 727182727184

5 - 1 where did I mess up?
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2. (Original post by ckfeister)
Attachment 727182727184

5 - 1 where did I mess up?
first line, you would have to raise e to the power of the whole left hand side.
It would be easier to first combine the two ln functions using the rule ln(a) + ln(b) = ln(ab)
3. Use the log properties to combine them:

ln(x+3) + ln(x-1) = 0

Hence, ln[(x+3)(x-1)] = 0

Can you continue it?
4. When you're applying something to an equation, e.g. adding a number, multiplying, dividing, any functions (taking ln, integrating, raising e to both sides, etc etc), you must do it to all of LHS and all of RHS respectively (not to each term).
5. (Original post by thekidwhogames)
Use the log properties to combine them:

ln(x+3) + ln(x-1) = 0

Hence, ln[(x+3)(x-1)] = 0
You know not to post full solutions - please edit your post.
6. (Original post by Muttley79)
You know not to post full solutions - please edit your post.
Ah sorry my bad, edited. But the answer was already provided and it was a showing question.

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