Need help with logs

[moyshekapoyre]

Hey guys, I don't understand how to solve for t in this equation:

5e[sup:10gmtw7k]3t[/sup:10gmtw7k]=8e[sup:10gmtw7k]2t[/sup:10gmtw7k]

The book says the answer is ln(8)-ln(5). I don't know how it gets that answer.

I get this far:

3t*ln(5e)=2t*ln(8e)
=
3t/2t=(ln(8) + 1) / (ln(5) + 1)

Ok this is not helping me solve for t. So obviously I don't get something really basic. Any help is much appreciated! I have a quiz on Tuesday and this is the one thing I don't understand in the problems.

 

[mmm4444bot]

5e[sup:2cwri9hs]3t[/sup:2cwri9hs]=8e[sup:2cwri9hs]2t[/sup:2cwri9hs]

The book says the answer is ln(8)-ln(5). I don't know how it gets that answer.

Hoy Moy:

Hint 1: Since e^(2t) is non-zero for all Real t, we can begin by dividing both sides by e^(2t)

Hint 2: Property of exponents: e^n/e^m = e^(n - m)

Hint 3: Property of logarithms: ln(a/b) = ln(a) - ln(b)

Cheers ~ Mark

 

[Deleted member 4993]

Hey guys, I don't understand how to solve for t in this equation:

5e[sup:2azu4mdf]3t[/sup:2azu4mdf]=8e[sup:2azu4mdf]2t[/sup:2azu4mdf]

The book says the answer is ln(8)-ln(5). I don't know how it gets that answer.

I get this far:

3t*ln(5e)=2t*ln(8e)
=__________________________
5e[sup:2azu4mdf]3t[/sup:2azu4mdf] = 8e[sup:2azu4mdf]2t[/sup:2azu4mdf]

ln {5 * e[sup:2azu4mdf]3t[/sup:2azu4mdf]} = ln {8 * e[sup:2azu4mdf]2t[/sup:2azu4mdf]}

ln {5} + ln{e[sup:2azu4mdf]3t[/sup:2azu4mdf]} = ln {8} + ln{ e[sup:2azu4mdf]2t[/sup:2azu4mdf]}

ln {5} + 3*t*ln{e} = ln {8} + 2*t*ln{e}

ln {5} + 3*t = ln {8} + 2*t

You need a serious review of "log" properties.....
____________________________________________
Ok this is not helping me solve for t. So obviously I don't get something really basic. Any help is much appreciated! I have a quiz on Tuesday and this is the one thing I don't understand in the problems.

 

[moyshekapoyre]

Thanks guys

It's really weird, when I looked at the answer in the last post, by Subhotosh, there was nothing in there that wasn't obvious. It's not like I didn't know all those log properties, but SOMEHOW the most obvious stuff was just escaping me until I read that. I couldn't believe I hadn't done exactly what Subhotosh did. Am I the only one that gets these long brain freezes? Is it a nutritional deficiency?

 

[Denis]

Don't feel bad...happens to most of us (except Mark!).

Couple years ago, I had x^(a+1) = x^(7), was getting ready for a complicated "attack"
in order to solve (for my grandson: 14 then), when he said: isn't that simply a+1 = 7 ? :shock:

 

[futurerainbow]

I need immediate help with square root problems in college

I am in college and barely making it through my algebra class. Can someone please help me get through this chapter at least, dealing with square root problems??

I am not sure how to do the symbols in this forum but it is as follows:

6x (outside the sq.root symbol) 32z^5=inside the sq.root symbol then -z^2 and then another sq.root symbol with 8zx^2 inside of the symbol.

I hope this makes sense and that someone can help me immediately.

Thank you for your time.

 

[Denis]

Please start your own thread.
And deal with square roots this way: sqrt(something).

 

[Aladdin]

Don't feel bad...happens to most of us (except Mark!).

Couple years ago, I had x^(a+1) = x^(7), was getting ready for a complicated "attack"
in order to solve (for my grandson: 14 then), when he said: isn't that simply a+1 = 7 ? :shock:

- - - Love your grandson - - -

 

[Denis]

..........................Hits - Outs - Walks - Batting Average - On Base Average

                                    H    O    W      BA    OBA
Spring league                       6   10   10    .375   .615
Pinecrest Tournament                5    6    3    .455   .570
NDG Tournament                      2    2    4    .500   .750
Summer league                       4    5    5    .445   .640
League playoffs                     3    2    3    .600   .750
District playoffs                   6    6    4    .500   .625
Provincial playoffs                 9   14    2    .390   .440
National playoffs                   4    6    2    .400   .500
 
Combined                           39    51  33    .433   .585

And I'm VERY proud of him; above are his baseball stats this year.
His team made it to the Canadian championship (Nationals);
didn't win that: British Columbia did (no snow there!).