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1. The starting question is solve; 2log3x-log3(x-2)=2 [x>2]

I understand how to get to the point log3(x2/x-2)=2 , but from here on I'm stumped

The next point is x2/x-2=32 , but I don't know why it goes from the previous to this, please explain

Thank you :P
2. (Original post by IndiaJones)
The starting question is solve; 2log3x-log3(x-2)=2 [x>2]

I understand how to get to the point log3(x2/x-2)=x , but from here on I'm stumped

Why has the 2 turned into an x?
3. (Original post by TenOfThem)
Why has the 2 turned into an x?
...typo or witch-craft, you choose
4. (Original post by IndiaJones)
...typo or witch-craft, you choose
ok.
5. (Original post by IndiaJones)
The starting question is solve; 2log3x-log3(x-2)=2 [x>2]

I understand how to get to the point log3(x2/x-2)=2 , but from here on I'm stumped

The next point is x2/x-2=32 , but I don't know why it goes from the previous to this, please explain

Thank you :P
inv log both sides (i.e. make them powers of 3) and you get a simple quadratic
6. (Original post by IndiaJones)
The starting question is solve; 2log3x-log3(x-2)=2 [x>2]

I understand how to get to the point log3(x2/x-2)=2 , but from here on I'm stumped

The next point is x2/x-2=32 , but I don't know why it goes from the previous to this, please explain

Thank you :P
Oh I had not realised you were still confused now that you have edited your error

means

7. (Original post by IndiaJones)
The starting question is solve; 2log3x-log3(x-2)=2 [x>2]

I understand how to get to the point log3(x2/x-2)=2 , but from here on I'm stumped

The next point is x2/x-2=32 , but I don't know why it goes from the previous to this, please explain

Thank you :P
because logax=b therefore ab=x

a=3 , x=x2/x-2 , b=2

so x2/x-2=3​2
8. log3(x^2/x-2)=2 will change to 3^2=(x^2/x-2) using the rule above, then you can turn it into a simple quadratic equation (x^2 - 9x + 18 = 0) and solve fully it from there
9. So that's four people who've provided the answer now
10. (Original post by ellen123abc)
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(Original post by Plato's Trousers)
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(Original post by TenOfThem)
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(Original post by XTRdigital)
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Thank you all, I didn't expect so many helpful people
11. (Original post by IndiaJones)
Thank you all, I didn't expect so many helpful people
yeah. we're all great on here

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