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#1 2006-11-07 12:35:23

unique
Member
Registered: 2006-10-04
Posts: 419

evaluate

very long.......help

4
-- log8 32 - log8 ( x + 2) = log8 2
5


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#2 2006-11-08 01:58:17

mathsyperson
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Registered: 2005-06-22
Posts: 4,900

Re: evaluate

You can use various laws of logs to help you out here.

The first term is 4/5 log 32. But that is equivalent to log[32^(4/5)], which works out nicely as log 16.

Now you can rearrange to get the x term on its own: log 16 - log 2 = log (x+2).

Using another log law you can combine the two logs on the left side to get log (16/2), which is log 8.

And now you've just got one log term on each side, you can take exponentials to get rid of the logs. 8 = (x+2)  -->  x = 6.


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#3 2006-11-08 03:21:06

unique
Member
Registered: 2006-10-04
Posts: 419

Re: evaluate

this is much hard....
the other log problems looked much eaiser than this.


Desi
Raat Key Rani !

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