３つの黒い線分が1点で交わるように
四角い頂点を動かしてみよう．

そのときの辺の比の計算がどうなるかを
観察しよう．

×

×

チェバの定理

A = (4.54, 4.8)
B = (-1.98, -3.58)
a = Segment(A, B)
C = (10.7, -4.66)
b = Segment(C, A)
c = Segment(B, C)
Q = Point(c)
R = Point(b)
P = Point(a)
d = Segment(P, C)
e = Segment(B, R)
f = Segment(A, Q)
g = Segment(A, P)
h = Segment(P, B)
i = Segment(B, Q)
j = Segment(Q, C)
k = Segment(C, R)
l = Segment(A, R)
テキスト2: "" + h + ""
テキスト3: "" + j + ""
テキスト4: "" + l + ""
テキスト5: "" + i + ""
テキスト6: "" + k + ""
テキスト1: "" + g + ""
m: g * i * k / h / j / l
G = (7.72, 5.06)
H = (9.28, 5.06)
n = Segment(G, H)
I = (9.76, 5.06)
J = (11.38, 5.06)
p = Segment(I, J)
K = (11.84, 5.06)
L = (13.42, 5.08)
q = Segment(K, L)
テキスト7: "=" + m + ""