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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
Desi
Raat Key Rani !
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#2 2006-11-08 01:58:17
- mathsyperson
- Moderator
- 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.
Why did the vector cross the road?
It wanted to be normal.
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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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