Use the Pythagorean theorem and the
definition of an ellipse, show that
r=(a(1-e^(2)))/(1+ecos heta )
Hint: Two right triangles are in this picture, sharing one side. Write down the Pythagorean
theorem for the right triangle with r^(') as its hypotenuse. Use the smaller right triangle to
introduce the angle heta into the problem.
4. Use the Pythagorean theorem and the definition of an ellipse. show that
a(1= e2) 1+ e cos 0
an
Hint: Two right triangles are in this picture, sharing one side. Write down the Pythagorean theorem for the right triangle with r' as its hypotenuse. Use the smaller right triangle to introduce the angle 0 into the problem