David Marain

@repmarkpocan It's a tragedy when any child is killed but denying facts to further your narrative is destroying this nation and must be challenged EVERY TIME. snopes.com/fact-check/hav…

4.14159… Is 83,521 divisible by 17? 1) 8352 - 1x5 = 8347 2) 834- 7x5 = 799 3) 79 - 9x5 = 34✅ Make a conjecture about a rule for divisibility by 17 based on this example and test it with three other numbers. Proof? @asitnof @HarMath @RaminKhosravi4 @mATH_e_matics @NCTM

ADJACENCY, PROBABILITY AND A PATTERN @scodiu @asitnof @DonFraser9 @mATH_e_matics @PerHenrikChris1 @HarMath @howie_hua @RaminKhosravi4 @NCTM @maanow @mathillustrated @MathCurmudgeon

1.1415… @scodiu @asitnof @DonFraser9 @mATH_e_matics @PerHenrikChris1 @HarMath @howie_hua @RaminKhosravi4 @NCTM @maanow @mathillustrated @MathCurmudgeon

SAME LIMIT INTEGRAL, DIFFERENT VIDEO PRESENTATION. MORE LEGIBLE, APPEALING??

MORE THAN JUST A CHALLENGING INTEGRAL PROBLEM… @asitnof @DonFraser9 @mATH_e_matics @jamestanton @NCTM @MrValencia24 @maanow @RaminKhosravi4

3,5,15,75,1125,… Before attempting that challenge, watch the video below… @asitnof @DonFraser9 @mATH_e_matics @jamestanton @NCTM @MrValencia24 @maanow @RaminKhosravi4

THE MYSTERIES OF 8n+1 @asitnof @DonFraser9 @mATH_e_matics @jamestanton @NCTM @MrValencia24 @maanow @RaminKhosravi4

@howie_hua 15^2 - 3^2 = 225 - 9 = 216 (6•2)•(6•3) = 6•6•6 = 6^3 = 216

It's Mental Math Monday! How would you mentally calculate 12×18?

Please comment on whether you find these videos useful or the AI voice is a turn off and most people would prefer seeing a human at a whiteboard explaining the details

NON-PRIMES AS A SUM OF SQUARES? @asitnof @DonFraser9 @mATH_e_matics @jamestanton @NCTM @MrValencia24 @maanow @RaminKhosravi4

A PYTHAGOREAN ‘QUAD GOD’? 3-4-12-13 @jamestanton @asitnof @PerHenrikChris1 @RaminKhosravi4 @dment37 @DonFraser9 @MatildaSpicer @NCTM @maanow @mATH_e_matics @ybgoi @howie_hua @HarMath @Jd2718x

@steph_bernard69 @MatildaSpicer Wonderful geometry problem from @MatildaSpicer and equally wonderful solution from Stéphane. I did not immediately see that ∠ AOB (not drawn) is a central angle of the larger circle AND an inscribed angle in the smaller circle which ⇒ arc AB from smaller circle is 132°

Let O be the center of the larger circle. If ∠ACB=33°, find ∠AFB. #mathpuzzle #Geometry #GeometricProblem

VEDIC MATHS! I didn't put my YouTube handle into the post yet. When I upload the full version with explanation and extension to other divisors, I will let you know!

The beauty of mathematics or just a trick? @asitnof @DonFraser9 @mATH_e_matics @ybgoi @howie_hua @PerHenrikChris1 @HarMath @RaminKhosravi4 @jamestanton @dment37 @sonukg4indi @nctm @maano

AN INTRIGUING COINCIDENCE? FOR STUDENTS [Comments? Reactions?] @asitnof @DonFraser9 @mATH_e_matics @ybgoi @howie_hua @PerHenrikChris1 @HarMath @RaminKhosravi4 @jamestanton @dment37 @sonukg4india @nctm @maanow

Thank you for the like, @PerHenrikChris1 😊

AN INTERESTING RELATIONSHIP IN CIRCLES @asitnof @DonFraser9 @mATH_e_matics @ybgoi @howie_hua @PerHenrikChris1 @HarMath @RaminKhosravi4 @jamestanton @dment37 @sonukg4india @nctm @maanow

'CHAIN 'OF REASONING IN CALCULUS [Note: Some of the expressions may be too long to fit on your screen] @asitnof @DonFraser9 @mATH_e_matics @ybgoi @PerHenrikChris1 @HarMath @RaminKhosravi4 @NCTM @sonukg4india @jamestanton @MathCurmudgeon @apcalc @apcalculusabbc @stevenstrogatz

Just to clarify - each of these videos that I am creating requires extensive planning and multiple revisions, although I am moving more toward using my own voice rather than the AI voice. I would appreciate constructive criticism.

COSINE and SINE HAVE THE 'BASIS' OF A PERFECT CALCULUS RELATIONSHIP! [Some parts of the video require more background and explanations are minimal] @asitnof @DonFraser9 @PerHenrikChris1 @HarMath @mATH_e_matics @ybgoi @RaminKhosravi4 @dment37 @jamestanton @sonukg4india @NCTM

@jamestanton @asitnof @DonFraser9 @PerHenrikChris1 @HarMath @mATH_e_matics @ybgoi @RaminKhosravi4 @dment37 @sonukg4india @NCTM Thank you, JAMES. The original video was longer and did get into the complex exponential solutions but I had to abridge!

@dmarain @asitnof @DonFraser9 @PerHenrikChris1 @HarMath @mATH_e_matics @ybgoi @RaminKhosravi4 @dment37 @sonukg4india @NCTM For fun, play with the solutions to Y' = kY, with Y(0)=1. This has solution Y= e^kx for all k. But for k = i (if this is allowed!) it also has solution Y = cos(x) + i sin(x). So ... e^ix = cos(x) + i sin(x) ??