$\large %n$

$\large %n$

$\large %n$

$\large %v$

$\large %v$

演示

F_1 = (0, 0)
c = Circle(F_1, 3)
F_2 = (2, 0)
k = 1 (slider from 0 to k')
C = Point(c, k)
f = Segment(C, F_2)
g = Segment(C, F_1)
M = Intersect(LineBisector[f], g)
i = Segment(F_2, M)
k' = 1 (slider from 0 to 1)
loc1 = Locus(M, k)
h = Segment(F_1, M)
text1: "|MF_1|+|MF_2|=" + (LaTeX[h]) + "+" + (LaTeX[i]) + "=" + (LaTeX[i + h]) + ""
A = Midpoint(C, F_2)

Tool: 简易坐标系
请选择原点，分别输入：x最小、最大值，y最小、最大值
Input: A, a, b, c, d
Output: B, C, O, u, v

$\huge\textcolor{}{x}$

$\huge\textcolor{}{y}$

$\Large\textcolor{}{O}$

A: (0, 0)
u = Vector(A + (a - 1, 0), A + (b + 1, 0))
v = Vector(A + (0, c - 1), A + (0, d + 1))
B: A + (b + 1, 0)
C: A + (0, d + 1)
O: A