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Can someone please explain how to solve a log equation with an example.
 one year ago
 one year ago
Can someone please explain how to solve a log equation with an example.
 one year ago
 one year ago

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dpaIncBest ResponseYou've already chosen the best response.0
how 'bout u pick an example....
 one year ago

dpaIncBest ResponseYou've already chosen the best response.0
otherwise i'll choose the easiest...:)
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
OK ... \[5^{x  3} . 3^{2x8} = 225\]
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
How to solve this using log? I'm new so I have no idea.
 one year ago

lgbasalloteBest ResponseYou've already chosen the best response.0
welcome to logarithms!
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
I guess you can solve this without using Logs..
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
But I want to know how to do it with log.
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Okay then all here will explain you how to do this...
 one year ago

moha_10Best ResponseYou've already chosen the best response.0
15^(x3)+(2x8)=225 now we take ln (3x11)15= ln225
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
What is In? And how did you get 15^(x3)+(2x8)=225?
 one year ago

moha_10Best ResponseYou've already chosen the best response.0
by multi 3 into 5 to get 15 and the exponent it's added
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
But how can you just multiply the base and add the exponents?
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Use the following formulas of Logs: \[\large Log(a \times b) = Log(a) + Log(b)\] \[\large Log(a)^b = b.Log(a)\]
 one year ago

moha_10Best ResponseYou've already chosen the best response.0
before we take the logarithem
 one year ago

moha_10Best ResponseYou've already chosen the best response.0
it's from exponent experepties
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
Why did you delete that @dpaInc?
 one year ago

dpaIncBest ResponseYou've already chosen the best response.0
because i don't wanna take away from these guys awesome explanations....:)
 one year ago

waterineyesBest 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..
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Use the first formula only...
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
\[\log(5^{x3}) . \log(3^{2x8}) = \log 225 \]
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Now Check my first formula carefully...
 one year ago

moha_10Best ResponseYou've already chosen the best response.0
@pratu043 trust take my answer
 one year ago

moha_10Best ResponseYou've already chosen the best response.0
like what waterineyes did now
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
That's what I've done here right @waterineyes?
 one year ago

waterineyesBest 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...
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
I've already done that. So now we should use the second one?
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
You have done it wrongly my friend...
 one year ago

waterineyesBest 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???
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
Oops. \[\log(5^{x3}) + \log(3^{2x8}) = \log225\]
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Yes now you are right... Now 225 is square of what number???
 one year ago

waterineyesBest 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..
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
\[\log(5^{x3}) + \log(3^{2x8}) = \log15^{2}\]
 one year ago

waterineyesBest 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??
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
I give you an example of that too: \[\large Log(x)^4 = 4.Log(x)\]
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
\[(x3)\log5 + (2x8)\log3 = 2\log15\]
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Can you write 15 as 3*5??
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
Yes. \[(x3)\log5 + (2x8)\log3 = 2\log(5 * 3)\]
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Then use it and use the first formula again on right hand side...
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
\[(x3)\log5 + (2x8)\log3 = 2\log5 + 2\log3\]
 one year ago

waterineyesBest 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??
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Tell me the coefficient of Log3 on Left hand side and right hand side...
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
On LHS its 2x  8 and on RHS its 2.
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Just equate them and find x from it..
 one year ago

waterineyesBest 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...
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
\[(2x8)\log3 = 2\log3\]
 one year ago

waterineyesBest 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...
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
So you should just do 2x8 = 2?
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
See, if : \[\large xlog3 = ylog3\] implies x = y. Getting??
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Yes you have found x = 5 that is absolutely right...
 one year ago

waterineyesBest ResponseYou've already chosen the best response.3
Now equate the coefficients of log5..
 one year ago

pratu043Best ResponseYou've already chosen the best response.1
x  3 = 2 x = 2 + 3 = 5
 one year ago

waterineyesBest 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??
 one year ago
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