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# Stuck on a Core 3 Logs Q (find x) Help :/ watch

1. How would you find x when:

(x+3/x-2) = e ?

2. I never used logs, instead I rearranged the left to say that 1 +(5/x-2) = e and solved from there. Not sure if this is allowed in C3 though :/
3. (Original post by mithili02)
How would you find x when:

(x+3/x-2) = e ?

How far have you got? Post your working.
4. Logs are necessary here. It's like using logs to solve .
Now e is just a constant so this is k=just like solving as an example.
5. You can get the answer for this without logs. Try multiplying both sides by the denominator, expand RHS, rearrange to get the x on one side and then factorise to get x(....), then divide both sides by the (....) to get x=.....

I just checked on the calculator and that works (sorry if that wasn't very clear)

You could take ln of both sides and since ln(a/b) = ln(a-b) you can:

rewrite as ln(x+3) - ln(x-2) = ln(e)

ln(x+3) = ln(e) + ln(x-2)

[ as ln(a) + ln(b)= ln(ab) ]

ln(x+3) = ln(e(x-2))

take e both sides to get

x+3 = e(x-2)

which is the same as if you just rearrange
6. Thankyouthankyou

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