Respuesta :
Answer:
α(t) = (-a*Sin(t), b*Cos (t)) where t ∈ [0, 2π]
Step-by-step explanation:
Given an arbitrary ellipse (x²/a²) + (y²/b²) = 1 (a, b > 0)
The parametrization can be as follows
x = -a*Sin(t)
y = b*Cos (t)
then
α(t) = (-a*Sin(t), b*Cos (t)) where t ∈ [0, 2π]
If t = 0
α(0) = (-a*Sin(0), b*Cos (0)) = (0, b)
If t = π/2
α(π/2) = (-a*Sin(π/2), b*Cos (π/2)) = (-a, 0)
If t = π
α(π) = (-a*Sin(π), b*Cos (π)) = (0, -b)
If t = 3π/2
α(3π/2) = (-a*Sin(3π/2), b*Cos (3π/2)) = (a, 0)
If t = 2π
α(2π) = (-a*Sin(2π), b*Cos (2π)) = (0, b)
We can see the sketch in the pic.

Answer:
Check below
Step-by-step explanation:
1) Firstly let's rewrite the equation for the sake of clarity, bearing in mind (a, b >0):
[tex]\frac{x^{2}}{a^2}+\frac{y^2}{b^2}=1[/tex]
a) To find a parametrization, to begin with we need to keep in mind this relations:
I)The general formula of the ellipse:
[tex]\\\frac{(x-p)^2}{a^2}+\frac{(y-q)^2}{b^2}=1[/tex]
II) Parametrization:
[tex]\left\{\begin{matrix}x(t)=acos(t)+p\\ y(t)=bsin(t)+p\end{matrix}\right.t\in[0,2\pi][/tex]
So, for that ellipse arbitrarily chosen we have:
p=0, q=0. So plugging in we have:
[tex]\left\{\begin{matrix}x(t)=acos(t)\\ y(t)=bsin(t)\end{matrix}\right.\:\:t\in[0,2\pi]\\[/tex]
For this exercise, suppose a ≠ b, and both >0
Since the Foci have the size of the minor axis over the longer one then
[tex]F_{1}=(-b,0), and \:F_{2}=(b,0)\\[/tex]
T values for F1, and F2
[tex]y=-bsin(t)\\\frac{y}{sin(t)}=-b\frac{sin(t)}{sin(t)}\Rightarrow \\\frac{y}{sin(t)}=-b\\\\\frac{1}{sin(t)}y=-b\\ \frac{1}{sin(t)}=\frac{-b}{y} \\F2 \\y=bsin(t)\\\frac{y}{sin(t)}=b\frac{sin(t)}{sin(t)}\Rightarrow \\\frac{y}{sin(t)}=-b\\\\\frac{1}{sin(t)}y=b\\ \frac{1}{sin(t)}=\frac{b}{y} \\[/tex]
