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The Hardest Log Question in the World..

right now, to me.

Calculate y for which 2log3 y - log3 (y+4) = 2

I expanded and got 2log3 y - ylog3 + 4log3 = 2

But I have no clue what to do next?

Do I do 2 - 4log3 ? :frown:

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How about this?

log3y2y+4=2\log_3 \frac{y^2}{y+4} = 2
That's so much better...>:frown: why didn't I think to do that!
Thank you!
Is 4log3 the sam as log(3^4) , though not too sure, not done C2 sice last year jan
Reply 5
y2/y+4=2 remember the division-minus rule, log3-log3=log3/3
Reply 6
and ylog3=log3^y
pesking2009
y2/y+4=2 remember the division-minus rule, log3-log3=log3/3

:nope:

=====> y2y+4=32 \frac{y^2}{y+4}=3^2
Reply 8
Lol at the thread title bit of an anticlimax :P GOod to see it get solved though on a serious note!
Reply 9
I would have been able to help with this, but I haven't done C2 since over an hour ago :biggrin:
Reply 10
log3(9) = 2
Reply 11
Whats with the sudden influx of log questions all of a sudden o_O
Reply 12
Ewan
Whats with the sudden influx of log questions all of a sudden o_O


c2 exam coming up and lots of people have trouble with logs.

I think the log questions in the actual C2 exams are rather easy though.

The mixed exercise in edexcel for logs is quite hard too.
Reply 13
Dam, I just had my C2 exam for the OCR paper. And my god, I feel like there's no hope.
You cancel out the like logs since it is. In base ten u cancel log3 out
Reply 15
Original post by Lawsonoluwaseun
You cancel out the like logs since it is. In base ten u cancel log3 out


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Original post by TeeEm
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Hahahaha so true
Original post by TeeEm
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Reminds me of when someone said, once differentiated to f'(x) = dy/dx, you can cancel the ds and get y = xf'(x)
This thread is 6 years old.
nice clickbait

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