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Comment Re:Journey to the Center of Dearth (Score 1) 199

Yep. Once I got out of the car, I sat down and wrote out the proof, which was indeed pretty simple algebra. Then I played around with some visual representations of the squares and other multiples using graph paper, which was briefly entertaining but not as educational. The main thing I kept from it was the mnemonic trick for occasional shortcuts. Sometimes it's easier to remember perfect squares or do a little subtraction in your head than to multiply large numbers.

Comment Re:Math education turns students off! (Score 1) 199

I would imagine it varies a lot from person to person. I really liked patterns, for one. Any time a sequence or series came up, I really enjoyed it. And the shapes, in geometry, but absolutely not the proofs. One of my favorite moments came in 5th grade, learning about different bases, and converting from one to another. I told myself then, "This is so much fun, I wish I could do it as a job." Curiously enough, a decade later I landed a job doing web design and did get to occasionally translate between decimal and hexidecimal for HTML colors. You could call it a dream come true, though I think some of the joy of converting bases had faded by then.

Comment Re:Journey to the Center of Dearth (Score 1) 199

I didn't have it quite that bad, but vaguely similar. My 6th grade math teacher realized I didn't need to be there and assigned me self-paced algebra instead. I was lazy, but eventually worked through quite a bit of the book. Then 7th grade came, and I was back in pre-algebra, before 8th grade had algebra again. I dealt with the boredom by reading novels through all of 7th and half of 8th grade (before it got ahead of where I had been) math. The teacher for 7-8 had mixed feelings, sometimes just letting me space out, other times pestering me to pay attention. She at least liked me, and supported me in the after-school math program, where I was an enthusiastic participant.

Random mathematical inquiry that you might enjoy: I once spent a road trip mucking around with a system of turning multiplication problems into subtraction problems, using the average and difference of two numbers and their squares. Perhaps better explained by example: I noticed that a pattern held where if you started with a number and squared it (for instance, 8 x 8 = 64) but then shifted the numbers up and down by 1 (9 x 7) the product was 1 less than the perfect square. If shifted by 2 (10 x 6) the product was 4 less, if shifted by 3 the product was 9 less (11 x 5 = 55), and so on, and this pattern held no matter what number you started with. Maybe a pointless trick, but a neat pattern, and I figured maybe someday I could win a bar bet by knowing that 254 x 258 is exactly 4 less than the square of 256 x 256, or that 195 x 205 is 25 less than 40,000.

It doesn't work so well if the numbers aren't an even number of steps apart, though, so most of the time was spent inventing placeholder techniques to compensate. For example, with 9 x 6 do I drop down it to an 8x6 problem and then make a note to add back in an 8, or do I bump it up to a 9x7 problem and then make a note to subtract the 9?

Comment Re:You must be new here (Score 1) 1830

I generally agree. I'd rather have more stories available, and then just ignore the ones I don't care about, than limit the selection. I even like the occasional borderline offtopic controversy, just because the discussions are generally interesting. It may be mostly unproductive, but even political flamefests are at least better argued here than most other places I visit on the web, and occasionally I learn a little something.

Comment Re:readers don't pay attention (Score 1) 165

In college, my speech teacher said "tell them what you're going to tell them, tell them, then tell them what you told them".

Your speech teacher was a hypocrite then. He should have said, "I'm going to tell you to tell them what you're going to tell them, and then I'm going to tell you to tell them, and then I'm going to tell you to tell them what you told them. Okay, with that out of the way, tell them what you're going to tell them, tell them, then tell them what you told them. In summary, I have told you to tell them what you're going to tell them, I have told you to tell them, and then I have told you to tell them what you told them."

Comment Re:Fast forward (Score 1) 255

Spoken by someone who has apparently never watched paint dry. Drips form quickly, basically almost immediately or soon after. You won't get one an hour later, let alone after 5. Wrinkles--and any other action--would happen in the first half hour, tops. After that, it might be a subtle change in sheen, or a little bit of blown debris that sticks, but that's it.

Confession: I once started a project called "Watching Paint Dry, and Other Adventures," which literally included a journal of my experience doing the titular deed, watching toasters toast, watching water boil, waiting in an airport, being stuck in traffic, etc. It was pretty funny, really, but it never made it past rough draft. But anyway that's immaterial to the discussion. I've painted a few houses and bits of furniture, and that's enough to know how it works.

Comment You Can Count on Monsters (Score 1) 238

The book, "You Can Count on Monsters" might be interesting. At 10, this might be nearing the edge of being too simple, but it's a book about prime numbers, factors, multiplication, sets, etc., presented with the numbers as monsters, with multiple visual depictions of how to imagine the numbers. For instance, the 6-monster is a combination of the 2-monster and the 3-monster, visually demonstrating that 6 is a combination of 3 and 2, whereas every prime number monster is visually distinct.

www.amazon.com/You-Can-Count-Monsters-Characters/dp/1470422093/

Disclaimer: my Mom either knows the person who did the book, or knows someone who knows the author. That's not why I recommended the book.

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