Help with graphing a conic problem....

[Yvo]

Before I start... this is not cheating or anything. I made sure with my math teacher that I was allowed to use helper applications on the test as showing work is still required. This is just to use if I am right or not.

So I use this TI-89 apps called Conic( http://endeavor.ticalc.org/objects/278.html ) but how in the world do I type in my equations... I am a total fool at this part.

For example a parabola equation in the book looks like x = y^2 - 4y + 1 in the but the program wants it in a(x-h)^2+k form.... or even simple ones such as x^2=-20y what is what exactly... because I am now confused.

Which is what variable??

Ellipses
Program equation:
(x-h)^2 __ (y-k)^2
------- + ------- = 1
a^2 ___ b^2

Book problem:

4x^2 + 25y^2 = 100 which is what variable??

last one...

Hyperbolas

Program:
(x-h)^2 _(y-k)^2
------- - ------- = 1 (other equation = y & x reversed)
a^2___b^2

Book problem:

y^2 _ x^2
--- - --- = 1
4___9

How am I supposed to define an undefined part of the problem (x & y) which it keeps asking for....

Any help would be greatly appreciated!!

Yvo

PS.... the board wont allow more then one space between text so some problems (such as the y over something problem) might look weird.

 

[Martin]

I'm not familiar with your graphing calculator, but most graphing calculators can only graph FUNCTIONS, ellipses and most hyperbolas are not functions, but relations. If yo want to graph them, you have to split them up and then graph each part seperately.


I'm too tired to do all your probs, but I'll solve the parabola one for you. Take the equation, complete the squre and you get "x=(y-2)^2 -3" Any parabola in this form is a sideways parabola and is a RELATION, not a function. This particular one will have its vertex @ (-3, 2) and will open to the right.




Also, I would suggest relying more on you REGULAR calculator, your brain and your knowledge of math, rather than on graphing calculators. Using graphing calculators when you dont know the concepts behind the math is very counterproductive.

 

[fyleow]

Haha that is like me, I know nothing about math and I still got an A. All because of my Ti-89. I figure I will learn this stuff one day, when I get burned on a test where no calculator is allowed.

 

[Martin]

I dont know what grade you guys are in, but if you plan to do anything even remotely connected to math you need to actually learn then concepts, rather than simply faking it.

Here is an interesting read for you guys.