Comment by 🚀 stack
Re: "Is there any particular reason why exponentiated negative…"
Yes, Python is widely used and there are tons of libraries to get things done. My main issue is that it pulls in gobs of stuff and I don't know what it is. Then something breaks because someone updates their library buried deeply in the system that I've never heard of. And I have to maintain 6 versions of Python itself, with yet another manager for just that.
Also as a language nerd I disagree with many fundamental choices made
But it's probably a decent way to get started and learn some bad habits.
Feb 24 · 2 months ago
5 Later Comments ↓
It comes up when you are deep in the tranches of the high school algebra, steadily working your way to a repetitive strain injury in one of your distal joints from chuirning through an endless onslaught of polynomials to simplify.
You'd encouner something like
666 - (x - y - x)^2
and cancel the x-es and get
666 - (-y)^2
and you must be carefull here to not go with your gut and be like "ah minus minus makes a plus", oh no, the square kills the minus, so it's
666 - y^2
would have been a whole different story if it was a cube... well just one sign flip... but that's what kills ya in them there the algebra trenches...
I think the convention is that exponent has a higher precedence than the minus sign, since the minus sign could also be used with other stuff before it to indicate subtraction.
This is the reason. if you have an expression like 5-x^2, you can rewrite the subtraction as addition and multiplication by negative one: = 5 + (-1)(x^2).
It's tempting to think of the minus sign as a part of the number, like the digits or the decimal point is. That's true enough if you're just dealing with an individual number, but once the minus sign is in a larger expression, it's much more helpful to look at the minus sign as an operator that means multiply by negative one.
🗡️ The_Jackal [OP] · Feb 25 at 16:38:
@namark Khan Academy plus looking at the comments on videos and elsewhere about the topic is what I've been using to relearn math so far. I'm considering seeing if going through IXL after Khan would really cement everything in my head just to be sure.
Khanacademy's good, glad it's sill alive. Khan is cool, made some nice math videos, radical revolutionary ideas on education, totally metal, but everyone else involved seems kind of meh, so they stalled. I remember vihart got involved at some point, and that's when I realized that all is lost - too happy, can't revolution when you are so happy. The website and the practise problems part are super lame, just get a decent book and do practice problems from there maybe idk, you are supposed to do a ton of them to get into the zone start churning through at some point, pressing your pen down way too hard from sheer adrenaline, can't do that with their sluggish web UI.
IXL never heard.
🗡️ The_Jackal [OP] · Feb 25 at 19:07:
@namark I'll probably look somewhere for practice books for different grades, or at least download a PDF of them. I had already decided after going through Khan and taking notes that I'd go back over everything with some good textbooks on the subject.
Original Post
Is there any particular reason why exponentiated negative numbers must be in parentheses like this: (-2)³ instead of being written like -2³? I looked around for a little bit and so far it seems like it's to show that it specifically shows that it's the result of negative 2 multiplying itself 3 times and not specifically the negative version of 2³. Is it to clear up ambiguity, like making sure you'd realize (-2)⁴ is 16 and not a round about way of saying negative 16 like -2⁴ might be interpreted...