LOGn() difficulties

[FedPete]

To me, this LOGn(), things came out of nowhere …

The step between X^y and it’s counterpart LOGx(n), goes to fast. Maybe to try to visualize it …?

[garypettie]

Hi @FedPete, apologies for missing your post, it was in the “ideas” section rather than “ask” (I’ve moved it for you).

Logarithms are the inverse of exponentiation, so you can think of them a bit like the undo button on raising a number to some power.
Just like how; multiplication and division, or addition and subtraction, are paired together. Exponents and logs are very closely linked, which is why they are introduced one after the other in the course.

Take the generic formula;
b^x = n

If you know b and n but not x, then you can find it with;
log_b(n) = x

For example, if;
e^x = 7.39

Then you can find x with;
ln(7.39) = 2

If you were to graph e^x and ln(x) you can see that they mirror each other nicely through y=x, which again shows how they are linked to one another:

I hope that helps explain why logarithms are so useful, but if you’d like some more detail then please let me know.

[FedPete]

Yes sure it helps me!
My last math lessons where many many years ago ;).
Back then I started with a slide rule.
Also based on this principle. And drawing graphs like these by hand.

It’s a fun course.

[garypettie]

Oh man, slide rules and log books!
Luckily I missed out on having to use them at school, but I was still taught how to use them as a child.
I’m glad to hear you’re having fun with the course!