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pratu043
Group Title
Can someone please explain how to solve a log equation with an example.
 2 years ago
 2 years ago
pratu043 Group Title
Can someone please explain how to solve a log equation with an example.
 2 years ago
 2 years ago

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dpaInc Group TitleBest ResponseYou've already chosen the best response.0
how 'bout u pick an example....
 2 years ago

dpaInc Group TitleBest ResponseYou've already chosen the best response.0
otherwise i'll choose the easiest...:)
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
OK ... \[5^{x  3} . 3^{2x8} = 225\]
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
How to solve this using log? I'm new so I have no idea.
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
I mean new to log.
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.0
welcome to logarithms!
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
Yeah thanks!
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
I guess you can solve this without using Logs..
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
But I want to know how to do it with log.
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Okay then all here will explain you how to do this...
 2 years ago

moha_10 Group TitleBest ResponseYou've already chosen the best response.0
15^(x3)+(2x8)=225 now we take ln (3x11)15= ln225
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
What is In? And how did you get 15^(x3)+(2x8)=225?
 2 years ago

moha_10 Group TitleBest ResponseYou've already chosen the best response.0
15*ln(3x11)=ln 225
 2 years ago

moha_10 Group TitleBest ResponseYou've already chosen the best response.0
by multi 3 into 5 to get 15 and the exponent it's added
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
But how can you just multiply the base and add the exponents?
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Use the following formulas of Logs: \[\large Log(a \times b) = Log(a) + Log(b)\] \[\large Log(a)^b = b.Log(a)\]
 2 years ago

moha_10 Group TitleBest ResponseYou've already chosen the best response.0
before we take the logarithem
 2 years ago

moha_10 Group TitleBest ResponseYou've already chosen the best response.0
it's from exponent experepties
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
Why did you delete that @dpaInc?
 2 years ago

dpaInc Group TitleBest ResponseYou've already chosen the best response.0
because i don't wanna take away from these guys awesome explanations....:)
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
See, take Log both the sides you will get: \[\large Log(5^{x3}.3^{2x8}) = Log(225)\] Now use the formulas I have written above..
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Use the first formula only...
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
\[\log(5^{x3}) . \log(3^{2x8}) = \log 225 \]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Now Check my first formula carefully...
 2 years ago

moha_10 Group TitleBest ResponseYou've already chosen the best response.0
@pratu043 trust take my answer
 2 years ago

moha_10 Group TitleBest ResponseYou've already chosen the best response.0
like what waterineyes did now
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
That's what I've done here right @waterineyes?
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
I give you an example: \[\large Log(2 \times 3) = Log(2) + Log(3)\] Go by this procedure...
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
I've already done that. So now we should use the second one?
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
You have done it wrongly my friend...
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
See check the formula.. After formula the result will be in sum form and your result is not in sum form.. Is there any + sign in your result???
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
Oops. \[\log(5^{x3}) + \log(3^{2x8}) = \log225\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Yes now you are right... Now 225 is square of what number???
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
So can you write 225 as \(15^2\) on right hand side.?? If yes then do it..
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
\[\log(5^{x3}) + \log(3^{2x8}) = \log15^{2}\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Now use the power rule of Logarithms that is the Second Formula that I have given above.. Can you use that??
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
I give you an example of that too: \[\large Log(x)^4 = 4.Log(x)\]
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
\[(x3)\log5 + (2x8)\log3 = 2\log15\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Can you write 15 as 3*5??
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
Yes. \[(x3)\log5 + (2x8)\log3 = 2\log(5 * 3)\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Then use it and use the first formula again on right hand side...
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
\[(x3)\log5 + (2x8)\log3 = 2\log5 + 2\log3\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Now what you have to do is to compare the coefficients of \(Log3\) and \(Log5\) both the sides can you do that??
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Tell me the coefficient of Log3 on Left hand side and right hand side...
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
On LHS its 2x  8 and on RHS its 2.
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Just equate them and find x from it..
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Similarly equate the coefficients of log5 and then also find x you will get the same x in both the case...
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
No no...
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
\[(2x8)\log3 = 2\log3\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
I said to equate the coefficients buddy.. Coefficients are 2x  8 and 2.. you should equate this only...
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
So you should just do 2x8 = 2?
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
See, if : \[\large xlog3 = ylog3\] implies x = y. Getting??
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Yes you have found x = 5 that is absolutely right...
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
Thanks a lot!!
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Now equate the coefficients of log5..
 2 years ago

pratu043 Group TitleBest ResponseYou've already chosen the best response.1
x  3 = 2 x = 2 + 3 = 5
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.3
Yes got the same value of x so you are right.. If anyhow x values are coming different then either question is wrong or your solution is wrong.. Getting??
 2 years ago
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