Please help me with this simple logs equation
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
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
(edited 10 years ago)
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
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?
Original post by TenOfThem
Why has the 2 turned into an x?
...typo or witch-craft, you choose
Original post by IndiaJones
...typo or witch-craft, you choose
ok.
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
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
(edited 10 years ago)
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
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
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
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=32
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
So that's four people who've provided the answer now 
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
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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