動圓上一點的軌跡
Author: 藍邦偉  老師

$ O $

1

$ 顯示\;P\;點軌跡 $

$ 動圓上一點的軌跡 $

$ P $

$ x=t+rcosθ $
    $=t+cos(-\frac{π}{2}-t)$
    $=t+cos(t+\frac{π}{2})$
    $=t-sint$

$ y=1+rsinθ $
    $=1-sin(t+\frac{π}{2})$
    $=1-cost$

2

$ 計算過程 $

u = Vector((x(Corner[1]), 0), (x(Corner[3]), 0))
v = Vector((0, y(Corner[1])), (0, y(Corner[3])))
O = (0, 0)
Q_2: 0.8 * Corner[1] + 0.2 * Corner[2]
Q_3: (x(Q_2), y(Corner[4]))
poly1, q_1, q_2, q_4, q_3 = Polygon(Corner[1], Q_2, Q_3, Corner[4])
t = 0 (slider from 0 to x(Corner[2]) + 1, step 0.0050)
C: (t, 1)
c = Circle(C, 1)
P: (t - sin(t), 1 - cos(t))
Q: (t - sin(t), 1 - cos(t))
a = false
b = false