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Mar 16 2015 11:59am
How do I draw this r=2cos(Ө)

is there something I could use instead of graphing calculator?

I don't own one and its a big problem for me and I don't even know how to draw these

This post was edited by twiiztedacer on Mar 16 2015 12:01pm
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Mar 16 2015 01:48pm
type 2cosx into gooogle
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Mar 16 2015 02:14pm
Since r = 2 cos θ, it follows that r^2= 2r cos θ. But r^2 = x^2 + y^2 and r cos θ = x, therefore
x^2 + y^2 = 2x. This can be rewritten as (x − 1)^2 + y^2 = 1 which is a circle of radius 1 with the center at (1, 0).

If you need further help with polar graphs, you can refer here: http://cims.nyu.edu/~kiryl/Precalculus/Section_8.2-Graphs%20of%20Polar%20Equations/Graphs%20of%20Polar%20Equations.pdf
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Mar 16 2015 03:14pm
Quote (JadeBlade23 @ Mar 16 2015 07:48pm)
type 2cosx into gooogle


does that rly work?
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Mar 16 2015 10:16pm
i know a pilot with a polar rout, but i get the feeling that's not what you mean.
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Mar 17 2015 11:34am
Quote (twiiztedacer @ Mar 16 2015 01:14pm)
does that rly work?

Google works for everything.

In this case, it's easier to use wolframalpha.com for your math questions.

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Mar 17 2015 12:32pm
Quote (Chibimaru @ Mar 17 2015 05:34pm)
Google works for everything.

In this case, it's easier to use wolframalpha.com for your math questions.

http://i61.tinypic.com/2uhu45s.jpg


its suppose to be a circle
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Mar 17 2015 12:40pm
Quote (twiiztedacer @ 17 Mar 2015 11:32)
its suppose to be a circle


Quote (twiiztedacer @ 17 Mar 2015 11:32)
its suppose to be a circle


Yah, you need to do it how I explained it to you. If you want extra help, feel free to send me a personal message. If you would like a program that helps you graph polar plots online, use this resource:

http://fooplot.com/#W3sidHlwZSI6MSwiZXEiOiIyY29zKHRoZXRhKSIsImNvbG9yIjoiIzAwODBjYyIsInRoZXRhbWluIjoiMCIsInRoZXRhbWF4IjoiMnBpIiwidGhldGFzdGVwIjoiLjAxIn0seyJ0eXBlIjoxMDAwfV0-
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Mar 17 2015 12:47pm
Jeffry has your correct response.

Quote (Chibimaru @ Mar 17 2015 01:34pm)
Google works for everything.

In this case, it's easier to use wolframalpha.com for your math questions.

http://i61.tinypic.com/2uhu45s.jpg


This is in Euclidean coordinates, not Polar coordinates.

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Mar 17 2015 04:02pm
Quote (Chibimaru @ Mar 17 2015 12:34pm)
Google works for everything.

In this case, it's easier to use wolframalpha.com for your math questions.

http://i61.tinypic.com/2uhu45s.jpg


This is incorrect.

Remember, polar coordinates give give r (DISTANCE from origin) as a function of theta (the angle). It should form a circle.

There are multiple ways to draw this graph. You can plug in your own values for theta (I would advise that you use values from the unit circle) or you can convert into (x,y) cartesian coordinates.

You will indeed see that as theta goes up, the radius stays constant and you will get a circle.

/e looks like Jeffry has you covered. You can always pm me if you want more polar coordinate help (he can probably help you as well, but don't pm him unless he gives you permission of course).

This post was edited by Casey on Mar 17 2015 04:04pm
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