Wednesday, December 12, 2007


Hey its Ant once again. Today we learned about ellipses. We started out by bringing out our previous drawn ellipse. which mine was stolen from my binder. Anyways later on in the class we drew a ling through the longest side of the ellipse through the center and named it "major axis". After wards we drew a line through the center again but this time perpendicular and through the shortest points of the ellipse.

Now how do we find the focus? well we determined length a is equal to the distance of A1 or A2 to the origin, and Length b is equal to the distance of B1 or B2 to the origin. We will call point F1 and F2 our focus. We know the Hypotenuse is Length a, and leg is equal to length b we can now use the Pythagorean theorem to solve for length c. By doing this we know the exact location of the focus. Because the distance from the center of the ellipse to the focus is length c. So now we know length c.

Now a little off topic but if we wanted to the value of P we could. Take length c and subtract it from Length a and we get a distance. that distance is P. Since earlier we learned the location of the focus = the appropriate value of the vertex + P. After we could also use distance P to find the directrix of the ellipse, on the other hand I don't have the slightest clue if ellipses have directrix but this is another way to look at an ellipse.

Anywho I am starving off to my 5th meal of the day. Next scribe is Miller "plasma grenade magnet"

'No prisoners!, No Mercy!"

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