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# Logs on left = Logs on right? watch

1. I didn't know this rule? Here I have a beasty equation mixed with logs and normal algebra, and apparently you can assume the logs on left = logs on right? Can someone please detail how this rule works please?
2. (Original post by Kev.1995)
I didn't know this rule? Here I have a beasty equation mixed with logs and normal algebra, and apparently you can assume the logs on left = logs on right? Can someone please detail how this rule works please?
Can you post the equation?
3. (Original post by Kev.1995)
I didn't know this rule? Here I have a beasty equation mixed with logs and normal algebra, and apparently you can assume the logs on left = logs on right? Can someone please detail how this rule works please?
You mean:

log(f(x)) + g(x) = log(h(x)) + j(x)

therefore log(f(x)) = log(h(x)) and g(x) = j(x)?

If so, no, you can't do that.

e.g. logbase2(1) + 2 = logbase2(4) + 0

But 2 =/= 0, and logbase2(1) =/= logbase2(4)

You can do it with complex numbers, e.g. a+bi = c+di, therefore bi = di and a = c, but that's because they belong to different sets of numbers.
4. here is the equation

sorry that it's upside down!
5. Please rotate it and reattach it kev.
6. (Original post by Kev.1995)
here is the equation

sorry that it's upside down!
No you cannot simply equate the ln parts

Can you post the actual question

(Original post by Mr M)
Please rotate it and reattach it kev.
It was easier to turn the iPad
7. oh come on, it takes likes two seconds to rotate the picture, at least do that before posting it
8. (Original post by TenOfThem)
It was easier to turn the iPad
9. when i open it up in photoshop it's the right way up, however on the thumbnail it's upside down!
10. thats only true if there are only logs on the RHS and on the LHS. A log is just a number. A weird representation probably.
So just like how
2=5 +P(x)
its not true to say 2=5
but 2=1+0.5+0.25+0.25
would be true. you could represent those numbers in terms of logs for some base im sure
11. (Original post by Kev.1995)
when i open it up in photoshop it's the right way up, however on the thumbnail it's upside down!
ok then

I'm sorry, I still don't get where you're going with this question, can you post the original?

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Updated: December 31, 2012
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