Mathematicians with tongue-in-cheek

Have you ever heard of the mathematician Niholas Bourbaki?

"Near the middle of the 20th century, Nicolas Bourbaki published several mathematics texts in areas such as Set Theory, Algebra, Topology, Functions of a Real Variable, etc. These texts had a profound impact on the mathematical landscape of the day and their affect is felt to this day."

So what's so important about Bourbaki?

Well, he never existed! It was just a tongue-in-cheek joke!

It's quite an interesting and funny story indeed... go read it at Natural Blogarithms.

Square root problem

prove that

5√20 × √45 × √5 = 150√5

This is a quite easy problem. You use two basic "ideas" or properties relating to square roots:

* that √b × b is b - or that you can "pull out" a number times itself from under the root (this is just the definition of a square root of course).

* that √a √b = √ab - or you can combine the radicands under the same root when they are multiplied.

So √20 * √45 is equal to √20*45 = √4 × 5 × 5 × 9
= √2 × 2 × 5 × 5 × 3 × 3 = 2 × 5 × 3 = 30.

So that's the crux of that problem.

Math Mammoth Grade 5 Worksheets ready

I hope you're not tired of hearing this.... but this is what I've been busy with lately.

Just as of today, I got Math Mammoth Grade 5 worksheets ready and available for purchasing.

Like the others, there are two separate books, A and B, plus answer keys.

Price for the whole package is $10. And that includes 123 quality math worksheets all total.

Click the link to see sample worksheets.

And, I've also set up a volume discount for any of my math books:

For order totals at least $34 - a 20% discount.
For order totals at least $50 - a 25% discount.
For order totals at least $70 - a 30% discount.
Use coupon code 8A2301338 when ordering to get these discounts.