# iteachmath math maths geometry proof cube sphere circles coremaths nctm sketched secondgrade imissmykids edtech mathedtech figurethat proofwithoutwords hsmath collegemath trigonometry mathed msmath trig geomchat 3d calculator augmentedreality 3dmodeling stem steam circle desmos funwithdesmos ipad arkit 3dmodel desmosart calculus apcalc lifeis3d whymodelonlyin2d precalc mathchat

1 triangle + 1 cevian + 3 circumcenters = 4 concyclic points! How to prove? 🤔 Source: . https://t.co/rRs3VoE0Y1

4 15
2020-07-09

Stereographic projection of circles by .

Consider the 8 vertices of the as points on the unit then make (spherical) centered on those points with radii chosen so that the circles are just tangent.

More➡️https://t.co/NjifiSyj0Y


16 36
2020-06-16

This was so fun last year, we used 's idea for his skee ball problem that I got from his session. Thanks Zak. It was such a fun task- I it. I love how their solutions looked so different ⚾️🥎🏀⚽️#secondgrade

1 2
2020-05-02

Interesting phenomenon that occurs in any triangle. How can we explain the occurrence of the angle bisector? 🤔 (Source: ) https://t.co/tpusqTwVCB

23 85
2020-03-19

Go ahead. Take a quick 0:41 break and experience traveling along the one & only side of a Möbius Strip. Created in & shown here in https://t.co/1vyp2ODIwf

42 97
2020-03-05

Atypical means for Ss to explore & discover laws of exponents? 🤔 Which surfaces match? Which don't? Could we use this logic just like many Ts have their Ss test for coinciding parabolas to see if quadratics are correctly factored?

9 15
2020-02-28

What causes a conic section to be a parabola? 🤔 Quick cause & effect demo in Why not give Ss opportunities to tell us what they see vs. us immediately telling them what to see? https://t.co/00lmQ6Y8Xc. For all conics: https://t.co/y0lB6Vf0FS.

23 56
2020-02-27

An unusual (not often seen) sufficient condition that guarantees a quadrilateral to be a parallelogram. How to prove? 🤔 Source: . https://t.co/WG1ElKNV2v

8 25
2020-02-15

Added a few more characters (PigPen, Woodstock, & Sally) to this year's holiday Peanuts dance. 🙂 https://t.co/bf8fDV4TV7

7 27
2019-12-26

cosine waves with square cross sections transformed into cosine waves with rhombus cross sections having interior angles measuring 60 deg & 120 deg. Created in on

16 44
2019-11-29

Here, the scene we New Englanders desperately miss this time of year. Now to go back and actually rock the boat... 🤔https://t.co/9j9N4LyDTw

7 15
2019-11-26

Custom Solid: Each cross section || yAxis = a parabola with latus rectum = upper(x) - lower(x). Upper & lower FNS, limits of integration all modifiable: https://t.co/RzVZjq4RWa. Shown here in w/#AugmentedReality.

6 10
2019-11-15

2 Cylinders + Hemisphere + Torus = Lamp ? More composite solid modeling in with More info re: getting started: https://t.co/tVhsrQbb4t

13 26
2019-11-12

What does it mean for a polygon to be CONVEX? CONCAVE? Here, a quick class opener using 2 different approaches: https://t.co/3M17XDndq2 Why tell Ss when they can explore themselves and tell us?

18 36
2019-10-31

sin(2v) = 2*sin(v)*cos(v): Dynamic & modifiable illustration using equal areas. For a quick investigation for Ss (w/o ID appearing at the end): https://t.co/hIaGZcseR3.

65 150
2019-09-09