Besides roots, logarithms, e, and pi, what other interesting "families" of irrational numbers are out there?
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📅︎ Nov 07 2020
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Other than the natural (base e), common (base 10) and binary (base 2), what are some other commonly used logarithm bases, and why?
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📅︎ Nov 24 2020
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Understanding difference between normal logarithm and discrete logarithm.

The wikipedia page on discrete logarithms is unclear to me. In the second sentence it says, " Analogously, in any group G, powers b^k can be defined for all integers k, and the discrete logarithm log(b,a) is an integer k such that b^k = a ". However, what is meant by "group" in this context and how is this definition different from your typical garden variety logarithm?

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📅︎ Dec 10 2020
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[Grade 12 Advanced Functions: Logarithms] How does the equation above simplify to the equation below? Teacher said it was the answer but didn't explain how.
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📅︎ Dec 06 2020
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How to calculate a logarithm by isolating the exponent?

Considering, for example: Log₂8= X, so 2^X = 8

I'm currently studying Python (a programming language) and currently I'm trying to challenge myself by calculating stuff like logarithms, factorials and etc without using pre-existing functions.

Computers are not capable of abstraction, so I can't write 2^X = 8 and ask for the X. I must isolate the X, then ask for it.

So, how do I do that?

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📅︎ Dec 09 2020
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Is there any way to do Logarithms such as Log63 or Log36 on my TI-nspire cx cas?

I am currently in a unit on Logarithms, and one of the directions is to evaluate to the nearest 100th.

On my nspire, hitting the Log key prompts a precoded formula. It looks something like LOG(base)(exponential).

When I receive problems like Log63 where you’re expected to find a decimal as an answer, I’m unable to get the answer, since my calculator presets the Log button to prompt a formula.

Is there a step that I’m missing or a sequence I have to do to find this solution? Help!

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📅︎ Dec 10 2020
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Can we take the logarithm of a negative number with a negative base?

I'm quite new to this topic and I'm curious if the question above is possible. Based on what I searched in the internet, you can't take the logarithm of a number with a negative base; and, the logarithm of a negative number is undefined. Does this mean that we can't take the logarithm of a negative number with a negative base?

Example is log(-64) with base (-4) = x. So if we transform it into a exponential equation and solve it further then it should be

(-4)^x = -64

(-4)^x = (-4)^3. Applying common base property of equality

x=3

Then log(-64) with base (-4) = 3

So it should be possible right?

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📅︎ Oct 09 2020
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Logarithm rules!!!
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📅︎ Dec 09 2020
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Derivation with logarithm

Could anyone explain, why exactly the derivation of y=e^ln(1+x^2) is 2x?

So y=e^ln(1+x^2) and y‘=2x, but why?

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📅︎ Nov 25 2020
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Exercises on complex logarithms

Hey guys!

We are just going through complex logarithms in uni and i believe i need to work to on some problems to get the hang of this. Do any of you know a good place to look for algebraic, non proof related exercises without buying a whole textbook? I googled a bit but couldn´t really find anything usefull.

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📅︎ Nov 27 2020
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How do I begin to answer this question on Logarithms [1st year science degree)?

The orbital velocity 𝑉 of a planet is related to its mean distance 𝐷 from the sun by the equation:

𝑉(2) =𝐺𝑀/𝐷

where 𝐺 is the gravitational constant, and 𝑀 is the mass of the sun.

If values of log(10) 𝑉 are plotted on the vertical axis on linear graph paper against values of log(10) 𝐷 on the horizontal axis for all the planets in the solar system, the points fall on a straight line with gradient 𝑚 and intercept 𝑐.

Explain, with appropriate algebra and equations, how the graph may be used to determine the mass of the sun.

Thanks for having a look.

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📅︎ Nov 26 2020
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eli5: What exactly is a logarithm?

Edit: thanks to all who replied! Y’all have really helped me with my math class- I don’t know how I got to precalc in college not understanding what these are, but I definitely get it much more than I did before. I’m too lazy to go to each response and thank y’all, so this is what I’m doing instead :)

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📅︎ Oct 14 2020
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Natural Logarithms and inequality questions

is (ln(a)/ln(b))>a/b always true?

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📅︎ Nov 23 2020
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Algebra Inverse Property of Logarithms

https://i.imgur.com/P2K6STg.jpg

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📅︎ Nov 15 2020
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Question about logarithm. Show that the equality is true.

https://gyazo.com/511e33e2191b04cd2366f866939ba543

Hi my friend just replaced h with h/2 on the left side and thus showed that this inequality is true. I am a little confused, am I really just allowed to do that? Dividing the left side with 2 would give me a different result right? I am really not familiar with logarithms.

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📅︎ Oct 21 2020
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Logarithms are going to absolutely destroy me.

It's the beginning of my school year and I'm barely making it and we're in the simple stuff for now, but doom, the logarithms, is near, and it's inevitable and unstoppable.

God help me.

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📅︎ Nov 16 2020
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Would like some help with logarithms

This is the question at hand :

If the equation log(ax)*log(bx)+1=0, with a > 0, b > 0, has a solution x > 0, it follows that b/a >= _____ or ____>=b/a>____

I partly arrived at the answer, this is my work :

since Log(ax)*Log(bx) = -1

we can assume one must equal +1 and the other must be -1, so:

log(ax)=1 ==> ax=10 ==> a=10/x

log(bx)=-1 ==> bx=1/10 ==> b=1/(10x)

now I will multiply b by 10 to get 10b=10/(10x), since a=(10/x), this can be written as :

10b=a/10

divide both by 10 to get b=a/100, thus, b/a=1/100.

this is partly correct, the real answer is that b/a>=100 OR

1/100>=b/a>=0

I honestly don't understand where the inequality is coming from and why b/a can be over 100.

ps: sorry for the poor formatting

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📅︎ Oct 29 2020
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Logarithm time
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📅︎ Apr 06 2020
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[Grade 10: Logarithms] How do you multiply logs together? I first expanded them using log laws and I tried the change of base formula but it hasn't gotten me anywhere. (Note that the logs are base x, a and b respectively)
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📅︎ Oct 15 2020
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Logarithms - How do you multiply logs together? I first expanded them using log laws and I tried the change of base formula but it hasn't gotten me anywhere. (Note that the logs are base x, a and b respectively)
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📅︎ Oct 15 2020
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📅︎ Aug 01 2020
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How to get good at Logarithms

How to get good at logs ? I find it hard to get used too.

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📅︎ Nov 04 2020
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