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benjamin dickman

@benjamindickman

K-12 math educator ๐Ÿช„โ™พ๏ธ Brookline to Nanjing to NYC Amherst College BA Fulbright Program x2 (๐Ÿ‡จ๐Ÿ‡ณ+๐Ÿ‡ต๐Ÿ‡ญ) Teachers College, Columbia University PhD past BU Wheelock (postdoc, Math Edu) cocreated original word game: #FiddleBrix http://tinyurl.com/bmdmaths

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Latest posts by benjamin dickman @benjamindickman

+1

09.03.2026 20:08 ๐Ÿ‘ 7 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

same #2solve, missed the mathier first word !

08.03.2026 14:24 ๐Ÿ‘ 3 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

DTMF ๐Ÿ“ธ

08.03.2026 01:09 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

FFTDMFFS

08.03.2026 01:06 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

rebumping

08.03.2026 01:03 ๐Ÿ‘ 0 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

The focus on reducing or eliminating "small agencies" can be extraordinarily misguided!

We had an incredible Office of Technology Assessment (OTA) that was eliminated amid the Gingrich R midterms for Clinton I. Still haven't recovered or revived it. Yet!

For more:
en.wikipedia.org/wiki/Office_...

07.03.2026 23:58 ๐Ÿ‘ 3 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

the math edu Mad ๐Ÿ†š Easy dichotomy... chime in!

#iTeachMath โ™พ๏ธ #MathSky ๐Ÿงฎ

07.03.2026 15:56 ๐Ÿ‘ 5 ๐Ÿ” 2 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

PPS: as a teacher, maddest (most irritated) would be radicals and variables. For example:

"Simplify: โˆš(xyยฒzยณwโด)"

Oftentimes, textbooks would give incorrect answers!

This one would be:
โˆš(xz) * |yz| * wยฒ

... does that even seem simpler?? I'm unconvinced.

Texts too often do e.g. โˆš(xโถ) = xยณ. False!

07.03.2026 15:40 ๐Ÿ‘ 3 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

PS: for integers a,b with no common prime factors, there are always integers p,q such that ap+bq=1.

The latter pair has no formal name despite being oft-used; same prof called p,q "Pavlovian integers" to *condition* students into considering their use.

For *years* I thought this was a common term!

07.03.2026 15:30 ๐Ÿ‘ 2 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

Easy: Figuring out whether a variety of Calc II sequences converge. Something that the professor, David Armacost (rip), taught to remind us that we only care about the long-term behavior was the acronym FFTDM (First Few Terms Don't Matter). This was certainly his own, original terminology ๐Ÿ˜†

07.03.2026 15:30 ๐Ÿ‘ 3 ๐Ÿ” 0 ๐Ÿ’ฌ 2 ๐Ÿ“Œ 0

Just remove the bottom left L and top right 7. Maybe modify the position means they can't be disappeared entirely (?) but they can certainly be moved such that none of those four is part of a square thereafter...

07.03.2026 15:20 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

quick Sat #2solve, an indefensible rise

01001101 01000001 01010100 01011010 01001111 01001000 00100000 01001000 01011001 01010000 01001111 01000011 01010010 01001001 01010011 01011001

07.03.2026 08:29 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

1990

05.03.2026 05:43 ๐Ÿ‘ 2 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

same Wed #2solve

salvadoreรฑo cansado

(the first word is a term sometimes used for people from El Salvador!)

05.03.2026 02:09 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

axiomatic trigonometry for intro to proofs?!
math.stackexchange.com/a/3310782/37...

direct link to the axioms:
drive.google.com/file/d/1rFkK...

(Axiom IV can be simplified slightly as described in the MSE post from me above)

#iTeachMath โ™พ๏ธ #MathSky ๐Ÿงฎ

04.03.2026 18:25 ๐Ÿ‘ 10 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

same Tue solve #2solve

๐Ÿซธ๐Ÿป๐Ÿ”ฅ๐Ÿชฒ๐Ÿซท๐Ÿป

04.03.2026 02:49 ๐Ÿ‘ 2 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0
Preview
Redactle | Wikipedia based Puzzle Game The most popular, fully featured, ad-free Redactle game! Daily puzzles with no ads, multiplayer, device sync, smart word matching and more. Your mission is to unveil the title of the redacted Wikipedi...

I solved Redactle #1426 in 30 guesses with an accuracy of 70.0% and a time of 3m53s. Play at redactle.net

03.03.2026 01:32 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

good problem!

02.03.2026 12:54 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

same tiny #2solve for Monday

02.03.2026 12:49 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

Sun #2solve; ululates on the beach

01001000 01001111 01010111 01001100 01010011 00100000 01010011 01010101 01001110 01000010 01000001 01001011 01001001 01001110 01000111

01.03.2026 08:43 ๐Ÿ‘ 2 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

Sat #2solve:
Almost Merlin (...Erlin?) and all that jazz

01001001 01011010 01000001 01010010 01000100 01010011 00100000 01010011 01000001 01011000 01001111 01010000 01001000 01001111 01001110 01001001 01010011 01010100

28.02.2026 09:07 ๐Ÿ‘ 0 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0
Big sky with a thin strip of land and some body of water, possibly the Susquehanna River. There are many clouds dispersed discretely but densely.

Big sky with a thin strip of land and some body of water, possibly the Susquehanna River. There are many clouds dispersed discretely but densely.

28.02.2026 04:06 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

re:
is this a problem mathematics can fix?

I enjoyed reading the various comments left, too. My view is that the numerics are often being used for a linguistic function (emphasis, juxtaposition, etc) rather than to communicate quantitative truths. And more often than not it's in bad faith!

27.02.2026 20:18 ๐Ÿ‘ 0 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

same but made a = 1/2 to deal w denominators only at the very end!

27.02.2026 11:35 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

e.g. this?
bsky.app/profile/benj...

27.02.2026 11:31 ๐Ÿ‘ 0 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

i don't follow how this "trick" was used? i see the final function but what computation was carried out to get there

27.02.2026 11:31 ๐Ÿ‘ 0 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

Ghausst

27.02.2026 11:26 ๐Ÿ‘ 0 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

i(-3+i) = -1 - 3i

xยฒ = 1 shift x to x+3i:
(x+3i)ยฒ = 1
xยฒ + 6ix - 10 = 0

change x to ix:
-xยฒ - 6x - 10 = 0

which is the quadratic found earlier, repeatedly (multiplied by -1)

so... the shift can be done by a complex value, too!

27.02.2026 11:25 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 0 ๐Ÿ“Œ 0

using
xยฒ = 9 for x = -3
then changing x to x-i:
xยฒ - 2ix - 10 = 0

gives the right root, but coefficients are not integral

would like to sub ix for x:
-xยฒ + 2x - 10 = 0

but this multiplies roots by -i

SO

instead we can start with desired root multiplied by i, and then use this method.

that is:

27.02.2026 11:25 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0

same Fri #2solve,

"โ†˜๏ธ๐Ÿ’‹"

27.02.2026 11:09 ๐Ÿ‘ 1 ๐Ÿ” 0 ๐Ÿ’ฌ 1 ๐Ÿ“Œ 0