Log Definition and 618 Threads

I am stuck on finding the solution to this problem. 2lnX = 2 + ln(X-1) Please show all steps for the solution. Thank you.

I'm working through an example problem wherein this bound is used: \left| \log \left( 1-\frac{1}{L^s}\right) \right| \leq L^{-\sigma}, where s:=\sigma +it and it is known that \sigma >1. How do I prove this? Should I assume the principle brach is taken?

Hi, I just need a little help in getting some sums. Can anyone of you give me a site where I can find sums in Log so that I can do them and practice a lot. I mean like sums in this type Show that log(xy)base16 = 1/2log(X)base4 + 1/2log(Y)base4 Thanks just need some sums of this type...

I'm taking cal 2 right now and i missed the part in cal 1 where he talked about "log theorem". Now this guy tells us that he's lazy when he corrects exams and if we don't use the log theorem to derive a term then he won't correct that term. I've looked on the net but couldn't find explanation or...

Hi, I am just a little confused with this log law of change base. Is there anyone who can give me a clear description with an example?:smile: Thanks

Hello everyone the problem I am messing up is: . Solve the following initial value problem: http://img59.imageshack.us/img59/9037/lastscan4vl.jpg When pluggin in answers and using my calculator to evaluate, its saying NON-REAL numbers, I'm messing up hardcore somewhere but not sure where...

Problem states: (A) Use mathematical induction to prove that for x\geq0 and any positive integer n. e^x\geq1+x+\frac{x^2}{2!}+...+\frac{x^n}{n!} (B) Use part (A) to show that e>2.7. (C) Use part (A) to show that \lim_{x\rightarrow\infty} \frac{e^x}{x^k} =...

If 3150g of a radioactive substance decays to 450g in 73 weeks, determine the half life of the substance to the nearest week. Solve algebraically using logarithms. 450=3150(x)^73 450/3150=x^73 73sqrt(450/3150)=x Now, the only problem is the answer says it is 26 weeks. Any help is much...

I have a tricky natural log in front of me. It's ln(1/x). The reason it's tricky is because I thought that I could re-write it as ln(1)-ln(x), as per the rules of logs, but that doesn't seem to agree with my calculator. Is there a reason why? Thanks!

http://img228.imageshack.us/img228/1799/untitled8av.png Kinda Tricky

I spent all of yesrterday going over a set of puzzles. One of them was: Assume you have a container divided into two equal sections (one on the left and one on the right). One section is filled with water and the other with air. A log is placed a long the divider between these two sections...

Ok, I worked this derivative problem, but my book has a different answer than what I got. I'm not sure why. I need to compute the derivative of log base3 of (x^3 + 2x) I came out with: 1/((x^3 + 2x)ln3) The book says that the answer is the same as mine except the numerator has a...

Hi i want to know if the log(10)(A/Ao)^10 gives 10*logA/Ao or 1 or 0

Hi all. I'm slightly confused with the following limit prob: \lim_{x\rightarrow \infty} \frac{(ln (x))^n}{x} which I know = 0. (n is a positive integer) It looks like it's of indeterminate form, that is \frac{\infty}{\infty} Using L'Hopital's, it looks like you get another indeterminate form...

What power must a man expend on a 100-kg log that he is dragging down a hillside at a speed of 0.50 m/s ? The hillside makes an angle of 20 degrees with the horizontal and the coefficient of friction is 0.9 m = 100kg v = 0.50 m/s \theta = 20 degrees \mu = 0.9 From here I thought that...

Graph Y1 = log (X^26) & Y2 = 26 Log (X) Are they Equivalent ? I drew the graph using X values ( -5, -4, -3, ... , 4, 5 ) and I got graphs, but don't know how to account for any differences in two functions.. Can anyone in here help

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oops wrong forum! Please move this thread...Q.1 Express in terms of the stated variable. If a = log (2) and b = log (3), what is log (25/9) in terms of a and b ? My work log (25) - log (9) = 2[log (5) - log (3)] And I don't know where to go from here. I tried a few different approach but can't...

I've been looking through my textbook for a question even remotly similar and no luck, if you could get me started witht this question I'd love to do it and then I'll write what I got and write it here. If y=x^2(a+z) determine an expression equal to log x. (Hint: you will need to take the...

Hey, here is a question I couldn't figure out. I think it's actually really easy, but the wording confuses me. A recent survey showed that the population, P, of Victoria is growing at an annual rate of 1.1%. Let P0 represent the population on January 1, 2001 and let t represent the time, in...

when trying to solve ln(x+4)=2 i tried this ln(x+4)=2 e^2=(x+4) ln e^2=ln(x+4) 2=ln(x+4) and round and round i go... where do i start to go wrong?

I have a class where I'm using the log function a lot, I would like to program a hot key to display log on my ti-89 for I don't have to mess with the catalog, any suggestions? Thanks Philip

Hello all. I am stuck on this homework problem. It wants me to find \frac {d^2y} {dx^2} when y= ln x^8 The book answer is \frac {-8}{x^2} But I only can get \frac {-8}{x^9)} Please give me some guidance Thanks

Whats the difference between log and ln?

Using log differentiation, find dy/dx, in terms of x for the following: y = (cosx)^sinx any help wud be appreciated, I am unsure of how to start this question, thanks in advance

How Do I Find The Logarithmic Expansions Of Log[x],i Mean The Series Of Log[x].it Is Urgent

This question should be easy to most people here and need some help on this question. 3log25 - log34 + log2(log39) My answer to this question is: = 3log25 - log34 + log2(log9/log3) = log2125 - log34 + log22 = log2125 - log34 + 1 = (log125 / log2) - (log4 / log3) + 1 = 6.703924778...

I can log on to any .tk website except for the main one http://www.dot.tk any help here?

Maths urgent help If there is a cubic log with a mass "M" and edges which have a length "2a" and is kept on top of a table,and there is a hole dug inside it right in between two parraral faces of this cube. This hole starts from the middle of one top edge(A) and leads on to the bottom of the...

hi guys, I am new to forums and need help cause I am doing engineering 1st year, and I am horrible at maths and chemistry (bad match :confused: ) equation is simple, x^2 Log x = 1, i have no idea wat to do with the 1 i turned it into x^2 log x -1 = 0 and then used y'=uv' + vu' and...

Help me solve for x in detail please: 8^x+13^x=108 Simply done graphically, but algebraically?

Can some one check my answers please? The answers are in my reply post at the bottom of this page THANKS :smile: I have a couple more log questions I am stuck on. They keep giving me log questions that they never showed me how to do.. very fustrating! I need to evaluate the following...

A while back in the school-year we were doing logs, and logarithm. We learned the power law, and such. It really annoys me when my teacher just throws something on the board like log and then shows us laws to remember. I don't even know what log is. Does it stand for a number? or is it just...

Ok so i was doing a problem involving finding the pressure of mercury at its boiling point (630.05K) using Troutons rule and the final answer seems a bit strange to me. Integration of the Clausius-Clapeyron Equation: {ln(\frac{{P}_{2}}{{P}_{1}}) =...

I have been working on this problem for a while. I am supposed to prove that log 2 = \lim_{n \rightarrow \infty} \frac{1}{n+1} + \frac{1}{n+2} + ... + \frac{1}{2^n}. The problem is that I have a hard time figuring out how I am supposed to prove that something is equal to a transcendental...

This is a quick graphing question. We have to graph Vout/Vin versus the log of frequency. Now the Vout/Vin would have no units but what about the log of frequency? Is it hertz or is it also unitless?

Suppose I burned a log. If I collected all the products of the burning process (the smoke particles, the ashes, etc.) would they have the same exact mass as my original log? Or would they have less mass because they are at a lower energy state then the original log (Energy-mass equivalence)...

b^x=y log_b(y)=x When you punch in log on your calculator, mathematically, how is it solving for x? For example, 3^x=81 log_3(81)=4 How is this being solved? Thanks

Can one under any circumstances say that log x^(-y) = -y ?? I'm having some truble with this myself, but someone told me it is so... :confused:

My physics teacher has posted log questions (for fun/frustration)almost every day. Having last had logs about 8 years ago, i have no clue how to solve for any of them. And seeing as how we don't actually use them in class, he won't help us figure them out. :bugeye: If anyone can offer me some...

I am rather confused by how the significant figure is suppose to work when you have logarithms in your equation. For example: Francium-87 undergoes beta decay with a half life of 22 min. How much of a 15.00 grams sample remains after 2.0 hours? Well, I used this equation: logA = log...

3 + 2 log (base 2) X = log (base 2) y how can this show, that y = 8X squared? Please help! :confused:

Is there a predefined function in C++ that will allow me to take LOG(base 10) of a number? If not, is there a reasonably simple work-around? thanks, MIH

Hello all If y = e^3^\ln^(x^2) find \frac {dy}{dx} So \frac {dy}{dx} =(3 (\frac {1}{x^2}) \* 2x e^3^\ln^(x^2) So the simplified answer is: \frac {6}{x} e^3^\ln^(x^2) Is this correct? IS there any other way of expressing the answer? Thanks

6-2x = 3 * log (x) Is it possible to solve such an equation without graphing?

Hi everyone! (d/dx) [xlnx] Why is the answer 1+lnx and not 1?? ~Thanks

Hi i was wondering if someone could check my work for these couple questions: Find dy/dx (do not simplify) a)y=e^sin3x dy/dx= e^sin3x (cos3x)(3) =3cos3xe^sin3x b)y=5^(square rootx) x^2 dy/dx=x5^(square rootx) (xln5+2) c)y=ln(x^2 / (2x+5)^3 ) y=lnx^2 - ln(2x+5)^3 dy/dx= 2x/x^2 -...

\text{Given that } log_b(x^3y)=p \text{ and } log_b(\frac{y}{x^2}) = q \text{ express } log_b(xy) \text{ in terms of p and q.} \text{ This is what I've done. } log_b(x^3y)=p----(1) log_b(\frac{y}{x^2})=q ----(2) 1 - 2 5log_bx=p-q \text{ I'm stuck here. What do I do next? }

Hello all, here is a problem I am working on that is giving me some problems. p,q, and N are defined as in RSA i.e. {p,q} in (Z_p,*), N = pq a in (Z_n,*) g in (Z_{N^2}) s.t. g=aN+1 mod N^2 The problem is to show that the discrete log problem base g is easy in Z_{N^2}, i.e. : given...

Hi there, I was hoping someone could check my solutions here to make sure I'm on the right track with these. We've been asked to find ALL values of z satisfying the following eqts - z= ln(-e^2) which I did by letting ln (-e^2)= ln|-e^2| + iarg(-e^2) = e^2 + i(pi + 2m(pi)) where m = 0...