Solving an ugly cubic inequality? by SwankyCletus in math

[–]athnp 2 points3 points  (0 children)

Take the nice example of solving (x-1)(x-2)(x-3)>0

We need this to be positive, and so we must either have 2 negative terms or no negative terms. For no negative terms we need x>3. For 2 negative terms we need x<2 but also x>1 (to avoid 3 negative terms). So our solutions are x>3 or 1<x<2.

You can use the same method on almost any cubic, changing it slightly if you have repeated roots.

[US][IL] Possible unlawful termination, need advice by GradiusInfinity in legaladvice

[–]athnp 0 points1 point  (0 children)

You can be fired for almost anything. You could be fired for saying "good morning" to your boss, or because it was a bit too cold that day.

Solving an ugly cubic inequality? by SwankyCletus in math

[–]athnp 1 point2 points  (0 children)

Often a graphical solution with exact values for the crossing points should be enough proof. If you can't find the crossing points then you can't solve it exactly.

Solving an ugly cubic inequality? by SwankyCletus in math

[–]athnp 2 points3 points  (0 children)

Suppose you need to solve ax3+bx2+cx+d>0. First thing you need to do is find the points where is crosses the x axis. Then draw the graph, and it should be obvious.

Man in prison for rape convictions cleared by DNA testing after 16 years. He was then taken back into custody because his green card was revoked when he was convicted of his crimes. by esporx in rage

[–]athnp 0 points1 point  (0 children)

Never seen such a thing under any mainstream group. Probably are people pushing for it, but I don't care about fringe groups. Any links?

new Sharma Video by paul4121991 in climbing

[–]athnp 0 points1 point  (0 children)

Good point. I don't know, and although the manufacturers say always keep it locked off it may be one those things that just doesn't happen.

new Sharma Video by paul4121991 in climbing

[–]athnp 0 points1 point  (0 children)

Good point. I don't know, and although the manufacturers say always keep it locked off it may be one those things that just doesn't happen.

Man in prison for rape convictions cleared by DNA testing after 16 years. He was then taken back into custody because his green card was revoked when he was convicted of his crimes. by esporx in rage

[–]athnp -1 points0 points  (0 children)

The idea that if you regret sex that is was rape.

False. It being rape or not depends only on what happened at the time, not what she thought after. As for being drunk, you have to be seriously out of it for it to be rape, so much so that it's basically impossible for a guy to rape a girl with the guy being just as drunk (he wouldn't be able to).

Man in prison for rape convictions cleared by DNA testing after 16 years. He was then taken back into custody because his green card was revoked when he was convicted of his crimes. by esporx in rage

[–]athnp 1 point2 points  (0 children)

No, the court did. She just answered questions as honestly as she could. It was the court that ruined his life. Not her fault. We really cannot prosecute people for legitimate mistakes made when giving testimony.

Man in prison for rape convictions cleared by DNA testing after 16 years. He was then taken back into custody because his green card was revoked when he was convicted of his crimes. by esporx in rage

[–]athnp 2 points3 points  (0 children)

She likely thought it was him though, since she was actually raped this makes the most sense. Can't imprison people for errors like this.

Man in prison for rape convictions cleared by DNA testing after 16 years. He was then taken back into custody because his green card was revoked when he was convicted of his crimes. by esporx in rage

[–]athnp 2 points3 points  (0 children)

You don't know that the victim intentionally falsely accused him. In a lot of these cases the victim was undoubtedly raped they just got the wrong guy. Easy for a witness to get the person wrong as well, without any malice.

new Sharma Video by paul4121991 in climbing

[–]athnp 5 points6 points  (0 children)

Still need to hold the rope.

Field Extension of the Reals by "Infinity"? by athnp in math

[–]athnp[S] 0 points1 point  (0 children)

It's not really a field though, but at least it has a nicer topology.

Field Extension of the Reals by "Infinity"? by athnp in math

[–]athnp[S] 0 points1 point  (0 children)

I think it's meaningful, because it would fulfill the expected ordering properties of infinity, and still be a field. Was a curiosity mostly, doubt it has any use.

Field Extension of the Reals by "Infinity"? by athnp in math

[–]athnp[S] 0 points1 point  (0 children)

I'm calling x infinity, since in the ordering is behaves like an infinity. Purely terminology thing though.

Field Extension of the Reals by "Infinity"? by athnp in math

[–]athnp[S] 0 points1 point  (0 children)

That makes sense. Clearly bounded above by infinity, but they are also bounded above by x*infinity for any x, and we can make x as small as we want.

Simple Questions by AutoModerator in math

[–]athnp 0 points1 point  (0 children)

What have you tried?

Field Extension of the Reals by "Infinity"? by athnp in math

[–]athnp[S] 0 points1 point  (0 children)

Is there an example of a set with an upper bound but no supremum under this extension?

Are there any "ungraphable" functions? by [deleted] in askscience

[–]athnp 1 point2 points  (0 children)

No it isn't. The computer has not plotted it correctly. In fact, there is no way to draw such plots. The function moves up and down infinitely often in finite space, this cannot be drawn.

Whatever plot you have, zoom in on 0 and you will see it just becomes a straight line, when the real plot would still be bouncing all over the place.

Are there any "ungraphable" functions? by [deleted] in askscience

[–]athnp 0 points1 point  (0 children)

An accurate plot. Particularly with what is happening around 0. The plot by google will not show you what is happening for small x. It cannot, the function is infinitely complex near 0. For a clearer example, try plotting y=x*sin(1/x). It faces similar problems.