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UnknownRandom
 one year ago
Could somebody help me with this log problem?
UnknownRandom
 one year ago
Could somebody help me with this log problem?

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UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.04log4(3)log4(4)

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0The answer can't contain a log

cutiecomittee123
 one year ago
Best ResponseYou've already chosen the best response.0I am really rusty and logs because I havent done them in a year or so. But I think you have to convert it to a diferent form inorder to solve it

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1familiar with the log properties ?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1alright apply log property start with the power rule

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1now set it equal to x or use change of base formula

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1if we set it equal to x we should change log to exponential form

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0I can't remember how to do that.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1for change of base formula \[\huge\rm log_b a = \frac{ \log a }{ \log b }\]

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1and if you want to do it by hands so set it equal to x dw:1443129484346:dw

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0dw:1443129612389:dw

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0Solving for that power?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1yes let missing exponent equal to x and then write 81 in terms of base 4

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.14 to the what power =81?

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0Wait, why can you cancel that 4?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1how would you cancel it ?

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0How did you get rid of that 4 in 81/4?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1we should rewrite 81 in terms of base 4 so we can apply the exponent rule \[\huge\rm \frac{ x^m }{ x^n }=x^{mn}\]

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1we need 4 base at the numerator so rewrite 81 in terms of base 4 4 to the what power = 81 ?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1ahh i see we can't write 81 in terms of base 4 3^4 = 81 i was thinking 4^3 sorry about that

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1well u have to take log to solve for x so jsut use change of base formula that would be easy

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0I was lost. The application we use to answer questions won't take answers with log in it. So what do you recommend?

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0How do write that?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1\[\huge\rm \log_\color{blue}{b} \color{ReD}{a} =\frac{ \log\color{red}{ a} }{ \log \color{blue}{b} }\]

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0log (81/4)/log(4)?

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0Do you subtract the two now?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1subtract no just divide them we don't need the original question

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0True, but on our test we can't use calculators so I don't know how I would do that division without one.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1can't use calculator hm i mean not just for log(4) ???

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0Nope, but we will probably be able to use log in our answers on the test.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1we have to use calculator for this one bec 81/ 4 is a decimal answer u were asking can we multiply 4 both sides ? yes you can dw:1443130983953:dw

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1when we multiply same bases we should `add` exponents \[\huge\rm x^m \times x^n=x^{m+n}\] \[\large\rm 4^1 \times 4^x =81 ~~~~~~~~~~4^{1+x}=81\]

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0So how do you find x?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1now take log both sides to move the exponent at front \[ \huge\rm (1+x )\log(4) = \log (81)\] now u can solve for x

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1divide both sides by log(4) and then subtract 1

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0Ok, I got 2.169925001 but it said the answer was wrong.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1http://www.wolframalpha.com/input/?i=4log4%283%29log4%284%29 that's the correct answer

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1is there any statement round some hundred/thousandth ?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1well i round it hundred place 2.169925001 (two numbers after decimal if the the 3rd is 5 or greater than 5 then we can wround to 7) 2.169925001 hundredths place 2.17

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1did they gave u the right answer ?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1ugh that's what i got and that's exactly what on this calc http://www.wolframalpha.com/input/?i=4log4%283%29log4%284%29

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0I don't know then. Thanks for the help though.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1alright ask ur teacher let me know what 's the correct answer if that's not right good luck!

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0I just typed 3/4 and it worked. Wow.... I guess the 4 wasn't supposed to be there on that problem. @Nnesha

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.13/4 ? what 4 wasn't supposed to be there ?

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0I guess not. Somebody done messed up.

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0and wasted 2 hours of my life.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1i don't get it so what was the question ?

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0The question was evaluate 4*log4(3)log4(4)

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1\[4 \log4(3)  \log4(4)\] like this or \[4\log_4 (3)  \log_4(4)\]

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1okay there is 4 at front of log so we have to apply the power rule right

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1so \[\log_4 (3)^4  \log_4 4 = \log_4 \frac{ (3)^4 }{ 4 }\] that's what we did so what was the mistake ? o.O hmm

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0I think it was typed wrong and the 4 in the front shouldn't have been there.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1oh okay so \[\large\rm \log_4 \frac{ 3 }{ 4 }\]

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0That's what I think.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1that will give u the negative answer

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1we can just guess if we don't know what the question is exly

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0\[4\log_4{3}1 \]

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.0So \[\frac{ \log3 }{ \log4 }1\]

UnknownRandom
 one year ago
Best ResponseYou've already chosen the best response.04^log4(3)log4(4) That is what the problem was supposed to say.

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1take a screenshot plz you're not sure abt the question ..
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