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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

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

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

Morley's Theorem - Dynamic & modifiable illustrator w/o words: https://t.co/se5j3nEutR. How to prove? 🤔

16 47
2019-05-18

And an arctan(1) & an arctan(2) & an arctan(1), arctan(2), arctan(3): HAPPY PI DAY!!! 😃 https://t.co/8BatAzK6Uj

2 4
2019-03-14

Any 1 Quadrilateral + Bisectors of its 4 Exterior Angles = 😮? How can we formally prove what is dynamically illustrated here? 🤔 (Source: ). https://t.co/27521S487E.

5 12
2019-02-25

In this incircle + extension animation, what is the measure of the green angle? Why is this ALWAYS the case? 🤔(Source: ) https://t.co/A6rEjBr5pT

3 5
2019-02-06

Carnot's - Case of an OBTUSE Dynamic Illustration without Words. How can we formally prove this phenomenon? 🤔(Source: ). https://t.co/qUDdwQwNTh

8 15
2019-01-31

Arc Length in Polar Coordinates (#Calculus): Dynamic & Modifiable Explorer & Illustrator. Created w/: https://t.co/OYvvLamA1y.

19 47
2019-01-23

In this animation, why are the 2 pink angles always congruent? (Source: ). Explore here: https://t.co/tpusqTwVCB.

4 9
2019-01-21

2 Concentric Semicircles + 2 Chords + 2 Perpendiculars = 😮? How can we formally prove these phenomena true? 🤔 Source: . Explore here: https://t.co/emj98BUbY4.

6 16
2018-12-28