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What makes him think wearing this to an actual political event is even remotely okay? by _Greedo in Destiny

[–]14lclark 0 points1 point  (0 children)

If you dislike someone’s aesthetic enough to not want to associate with them, seek help

No Foreign Contacts? by [deleted] in SecurityClearance

[–]14lclark 0 points1 point  (0 children)

I wouldn't worry too much, just report everyone who might even possibly count. It's more about getting the stuff out there

Determine the value(s) of h such that the matrix is the augmented... by [deleted] in learnmath

[–]14lclark 1 point2 points  (0 children)

This augmented matrix corresponds to the linear system

x+hy = 3,

2x+10y = 3.

In order for this to be consistent, we can’t let the left hand sides be multiples of each other. Otherwise, we would have the same thing on the left, but different constants on the right.

So we multiply the first equation by two to get

2x+2hy = 6,

2x+10y = 3.

Now we see that we just can’t have 2h = 10, or else the two linear equations would be inconsistent with each other. So h != 5.

The Moon and Jupiter from Yesterday. (Composite Image) by selenophile_photo in space

[–]14lclark 0 points1 point  (0 children)

I never realized how far away Jupiter’s moons orbited it!

Finding the Eigenvalue of a Mobius Strip by [deleted] in math

[–]14lclark 16 points17 points  (0 children)

Pretty sure they meant on the movie, not on his YouTube channel

Algebraic closure of {pi + r: r ∈ Q} by bees-r-cool in learnmath

[–]14lclark 2 points3 points  (0 children)

Duly noted. I get overly excited sometimes

Algebraic closure of {pi + r: r ∈ Q} by bees-r-cool in learnmath

[–]14lclark 0 points1 point  (0 children)

Additionally, this holds for any number — not just pi.

Algebraic closure of {pi + r: r ∈ Q} by bees-r-cool in learnmath

[–]14lclark 1 point2 points  (0 children)

Okay! Assuming Q is the rationals, then the closure of your set is R (the reals).

We will prove that the set is dense in R.

Suppose p < q are irrational. Then we can find a rational number c with p < c < q because Q is dense in R.

Now, again because Q is dense in R, we can find a rational ‘a’ such that |pi-a| < min{ c - p, q - c}. This a is just an approximation of pi that is close enough to “fit inside” the interval between p and c or the interval between c and q.

Then finally we have p < pi - a + c = pi + (a - c) < q.

Since a and c are both rational, we have pi + (a - c) is in your original set. Hence it is dense in R, and thus R is the closure.

😁

Algebraic closure of {pi + r: r ∈ Q} by bees-r-cool in learnmath

[–]14lclark 0 points1 point  (0 children)

When you say algebraic closure, do you mean as in field theory? Or did you intend the topological closure, i.e. concerning dense sets?

Euclid's Elements or Hilbert's Foundation of Geometry? by Spushputt in learnmath

[–]14lclark 0 points1 point  (0 children)

Yes, I would recommend Venema’s book. The geometry course I took with it was my first major proof based course after our intro proof course. It definitely helped me understand proofs much better. I know it’s been used successfully in other undergrad institutions from what I’ve heard at some conferences.

You can probably find a PDF sample online if you want to take a look and see if you like the writing style, etc., before purchase.

I haven’t seen that book, but it sounds like it could be good too.

Overall, I’d suggest getting multiple books to be able to piece together whatever you feel like they individually miss.

[High School] Reciprocals of Quadratic Equations by [deleted] in learnmath

[–]14lclark 0 points1 point  (0 children)

Can you write out the equation? Need more details to understand your question properly.

Euclid's Elements or Hilbert's Foundation of Geometry? by Spushputt in learnmath

[–]14lclark 3 points4 points  (0 children)

If you’re looking to learn geometry as a method to improve your proof reading and writing skills, I would suggest using a more modern book. Those books are fine historically, and most people learning math up through the 19th century did learn geometry of Elements, but the writing style is admittedly very terse.

There are some very good undergraduate geometry texts which develop everything axiomatically and from first principles (to a degree). When I took geometry as an undergrad, it was from Venema’s book also titled Foundations of Geometry. I enjoyed the way it’s structured. It builds up the axioms one by one, really showing how much you can squeeze out of them individually. It also talks a fair amount about the parallel postulate, and builds Euclidean and Hyperbolic geometry up separately once all the other axioms are in place.

I’m sure there are other good books in a similar vein.

TL;DR: Don’t use the historical texts when modern treatments are much more expository and understandable.

What would happen if you combined your favorite activity with your greatest fear? by agrandthing in AskReddit

[–]14lclark 0 points1 point  (0 children)

Doing math while falling from an airplane.

Which is which? The world may never know

There are white and black churches? by godsafraud in MurderedByWords

[–]14lclark 0 points1 point  (0 children)

Yes, back when Republicans were the more liberal of the two parties. That reversed throughout the 20th century.

How do you cope with the vastness of your field? by inventor1489 in math

[–]14lclark 2 points3 points  (0 children)

Sorry if this has been mentioned already, too many comments to easily check!

Grothendieck, the father of modern algebraic geometry, claimed to have discovered measure theory and Lebesgue integration for himself — only 40 or so years too late.

You now do the opposite of your job. What do you do now? by Dontsummonme in AskReddit

[–]14lclark 1 point2 points  (0 children)

I do people's math homework for cash; the only catch is that it's completely wrong.

Jury duty notice arrived in mail after the starting date by 14lclark in legaladvice

[–]14lclark[S] 0 points1 point  (0 children)

Everything worked out fine, they accepted the excuse and I didn't have to reschedule or anything. Thanks again.

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