Notes on ellipse

1. Equation:

• x^2/a^2 + y^2/b^2 = 1
• x(t) = a cos(t), y(t) = b sin(t)

2. Arc length:

• Integrate from t = 0 to t_0, sqrt[x'(t)^2 + y'(t)^2] dt
• Integrate from t = 0 to t_0, sqrt[a^2 sin(t)^2 + b^2 cos(t)^2] dt