I often post some links to interesting sites on Twitter, and once in a while I take the links I have collected and post them here as well for you to take a look at.  Here are a few links I have collected over the last few weeks.

Explanation of imaginary numbers. First of all I found an excellent explanation of what imaginary numbers are. The website is called betterexplained.com and I must say it lives up to the name.

Explanation of e: From the same site as before, a really good explanation of continuous growth and where e comes from.

Explanation of Euler’s formula: I read the two previous articles as a preparation for the sites explanation of Euler’s formula which states $e^{i\pi} = -1$.

Then I have a link to a small note on evaluating infinite sums. Goes through different kinds of series and how to evaluate them

Then I found a blog post with the title “The weirdness of infinity“, which talks about the mathematics of parallel mirrors. It is a rather interesting read.

That was it for now. I hope you enjoy the reading.

The photo is taken by Etrusia UK and shared under Creative commons license. The cropping I have made is shared under the same conditions.

### Posted by Kristian

SuprDewd

Now it’s pretty easy to see things like:
i * -i = 1

Thanks.
Btw. I like the new help text here below!

Kristian

Glad you liked i. I agree with you, for visual learners it gives a really good intuition for what imaginary numbers are.

I hope you and everyone else finds the help text useful, I decided to add it yesterday when I changed a few things anyway.

/Kristian