Proof of Feuerbach's Theorem

Tools used:
Inversion of circles
Nine-point circle
Orthogonal circles

[@user-qc7zu7lm7w]

Thank you so much, for all the effort you've put into this!

[@OsmanNal]

You are welcome.

[@lomertamahon1]

Excellent video.

[@tonyha8888]

Thankyou very much for your very good video!

[@chretiencustombassguitars6586]

hi Osman. just started checking out your vids.. Great work sir.. I need help on a proof of the following... A triad of Circles Tangent internally to a Nine Point Circle in an acute tringle's centres are colinear... any assistance will be appreciated

[@ujjwaljain4372]

I am new to inversions of circles and circumcircle mind not suggesting a resource where I can get to know what they really are

[@hustler2001]

sir,would u suggest some better geometry books together with an algebra book....`

[@quirtt]

Nice stuff.

[@shloksand2926]

Thanks Osman

[@johannesconradie1276]

What happens at 6:54? How do you conclude that statement? Very helpful video, but I'm stuck understanding why you claim so.

[@aman-qj5sx]

Same here

[@chen3587]

Same😩😩😩 I mean like this vid should be at least two times longer if you want to explain it clearly, I am really stuck......

[@shloksand2926]

I had a few problems in Geometry, Osman could you please help me solve them??

[@shloksand2926]

How do I contact you??They are quite challenging...

[@igml1145]

How do you exactly find the length of A'B"? We need to know also the length of BC1

[@igml1145]

I just realized that BC1=XY... I am gonna try to prove it tomorrow

[@OsmanNal]

AB=c and by symmetry AC1=b, thus BC1=b-c.

[@igml1145]

Osman Nal that is basically what i also did. Took me a while to notice that the sides of the triangle are in fact the common tangents

[@user-tn2dk2pg2p]

Do you know how you concluded the statement with similarity? Neither C' or B' are contained in those triangles.

[@chen3587]

@@user-tn2dk2pg2p That’s also where I got confused 🤷‍♂️