Sunday, May 26, 2013

Testing math notation

If $ax^2+bx+c=0$ with $a≠0$, then: $$x={-b±√{b^2-4ac}}/{2a}$$



  1. If you say so, Larry; my math skills really suck.

  2. That's the quadratic equation, which should be a part of every high school student's education. It is, in my opinion, extremely useful, perhaps necessary, to understand basic algebra. I've tutored a number of people in algebra, and I have never met anyone (who was neurotypical) who lacked the innate ability to understand algebra.

  3. Ah, well, I dropped out of high school fifty years ago, so perhaps it hadn't been invented yet. Basic math (addition, subtraction, multiplication and division) poses no problems for me, but as soon as the alphabet enters the mix math takes on mystical qualities similar to those I associate with electricity, which I don't fully grasp, either. My capacity for abstract thought seems to be limited to the things that can be defined by words rather than by mathematical symbolism. Still, there is a curious fact about the number 9 that doesn't apply to any other number.

  4. You would think it is part of every high school but it aint. I was instructing a class in basic electrical theory which is strong in algebra and noticed a couple of 20?somethings have a problem, and I asked was it that long from high school? their answer was 'never had algebra in high school, after picking my jaw up from the floor. I started teaching algebra. It is or was (5yr ago) so bad that I could put a simple algebra problem on the board, and ask, who can solve it? and then without looking state that everyone with their hand up is over 30 and 90% of them were.

    Hey Phil-if you under 75 it was there in most schools. The secret to algebra is to think of the formula as a sentence rather then math..I have some apples and want to divide them among a number of people, how many does each person have? Is the same thing as A/P=C C being the number of apples each person has.

    1. Thanks, L.L. I wrote partly in jest, but I do remember the quadratic equation from my high school daze--not the formula, per se, but "quadratic," a word rarely used in common speech.

      One of the most important lessons I've learned is that when one is confronted by a problem that seemingly lacks a solution, a change of perspective often provides one.

  5. You shouldn't be ashamed if you don't know algebra. It's worth learning, I think, because it's very cool. I tutor a number of people at my local community college (mostly for free; my primary educational job is as an English tutor), and when they start to get it, they light up. It really is fun when you get it.

    1. "It really is fun when you get it."

      Those words should be immortalized, Larry; almost everything is fun when you get it. A good education always gives native intelligence a boost.


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