Ipotesi\!:\ A\^BD \cong C\^BD

Tesi\!:\ \overline{AB} > \overline{AD};\ \overline{CB} > \overline{CD}

1\ -\ A\^DB > C\^BD\ -\ Teorema\ angolo\ esterno

2\ -\ A\^DB > A\^BD\ -\ Per\ (1)\ e\ (Ip.)

3\ -\ \overline{AB} > \overline{AD}\ -\ 
Teorema\ triangolo\ con\ angoli\ disuguali\ 
e\ (2)\ -\
\ \ \ \ \ \ \ prima\ parte\ Tesi

4\ -\ C\^DB > A\^BD\ -\ Teorema\ angolo\ esterno

5\ -\ C\^DB > C\^BD\ -\ Per\ (4)\ e\ (Ip.)

6\ -\ \overline{CB} > \overline{CD}\ -\ 
Teorema\ triangolo\ con\ angoli\ disuguali\ e\ (5)\
Q.\ E.\ D.

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A = (-0.7, 0.06)
B = (4.02, 0.06)
C = (0, 3.48)
poli1, c, a, b = Polygon(A, B, C)
D = Intersect(b, AngularBisector[A, B, C])
d = Segment(B, D)
α = Angle(C, B, D)
β = Angle(D, B, A)
γ = Angle(A, D, B)
δ = Angle(C, D, B)