Please help! Problem dealing with logarithms. Click attached
You will need to use a few log rules for this. 1. logx-logy=log(x/y) 2. zlogx=log(x^z)
yeah for this one only these two rules are needed. First try to make all the expressions in the form of log(something)-log(something else).... So get rid of the factors 3, 1/4, 1/2 using the 2. rule
If thats done you can use the first rule. Good luck! And remember x^(1/2) is equivalent to the square root of x
Thanks!
:/ Hmm... I think it's either the second or third but having trouble coming up with the correct final answer
Let look at it term by term 3logx=?
1
1? we dont know what x is, so the solution has to have x in it
x=1?
by rule2 3logx=log(x^3)
we dont know what x is, just imagine any number, but you cannot place!!!! any number there instead of x
that is called unknown or variable
so second part 1/4log y=?
(y is also unknown)
Yes. But why am I getting y=1? http://www.wolframalpha.com/input/?i=1%2F4logy%3D
that is its root, different thing It means that when y=1 1/4log y=0 That is called the root of a function, where its value is 0.
O.k. Now I get it
wolfram is a good tool but you still need to think
thats why we have a magical brain! :-)
:)
here your only goal is to simplify the log expressions into one log expression
you are not solving anything, it will be still the same thing just written differently. Some would say in a neater form. (I disagree but that doesnt matter now I guess)
so 1/4log y=?
logy/4?
that is wrong but better than 1 :) rule 2 was: zlogx=log(x^z) In our scenario z is given, it is 1/4 and x should be replaced by y
log(y^1/4) ?
Yes, you are getting there!
1/2logz=?
1/2log1/4=-/301?
?
1/2log1/4 where did this expression come from? Its like a rabbit from a hat
1/2logz=? where z is unknown, so z should not be replaced by a number!
I can see that these logs are killing you :D, I dont like them as well....
AHHHHHH! Yes they are lol Do you mind just going through solving the problem step by step? I'll follow along and can use it as an example
sure 1/2logz=log(z^1/2)
so we have 3logx=log(x^3) 1/4logy=log(y^1/4) 1/2logz=log(z^1/2)
now first two parts logx^3 -logy^1/4 (1. rule)= =log(x^3 /y^1/4)
log(x^3 /y^1/4) -logz^1/2= (1. rule again) =log){(x^3 /y^1/4) /z^1/2} simplify the middle part now x^3 /y^1/4) /z^1/2= (fraction over fraction is = to 1st fraction multiplied by the reciprocal of the 2nd fraction) =(x^3 /y^1/4) *z^1/2=(x^3*z^1/2)/y^1/4
so the solution is log(x^3*z^1/2)/y^1/4
A
Thank you so very much Andras :) I really appreciate your help and patience haha
Your welcome, hope it cleared up a bit
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