Finding Directrix and Sketching Hyperbola in Polar Coordinates

In summary, the given hyperbola formula is converted to rectangular form, with the coordinates of the vertices being (0,3) and (-4,3) and the coordinates of the foci being (-2+ sq. root 13,3) and (-2 + sq. root 13, 3). The eccentricity is (sq. root 13)/2. The directrix can be found using the formula x = (a^2)/c, but there may be some confusion in finding its location. In polar coordinates, the equation of the conic section is r = (sq. root 13)/2 *cos(theta), with the pole taken to be the leftmost focus. Sketching the hyperb
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Homework Statement


Hyperbola formula 9x^2 - 4y^2 + 36x + 24y - 36 = 0.
Convert to rectangular form, find coordinates of the vertices, find coordinates of the foci, find eccentricity, what is the equation of the conic section in polar coordinates if the pole is taken to be the leftmost focus? Sketch.

Homework Equations


a^2 +b^2 = c^2 directrix: x = (a^2)/c e = c/a

The Attempt at a Solution


So I have the hyperbola formula 9x^2 - 4y^2 + 36x + 24y - 36 = 0 I converted it to...
((x+2)^2)/4 - ((y-3)^2)/9 = 1
The vertices I have as (0,3) and (-4,3)
The foci I have as (-2+ sq. root 13,3) and (-2 + sq. root 13, 3)
Eccentricity is (sq. root 13)/2
Now here's the problem I'm having issues trying to find the directrix. I found a formula that says its x = (a^2)/c so after plugging in I get 1.109 but that's between the right vertex and right focus, aren't the directrixes suppose to be between the center and the vertices. Also I'm not quite sure what to do "the pole is taken to be the leftmost focus."
 
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The equation of the conic section in polar coordinates is r = (sq. root 13)/2 *cos(theta)I'm having a hard time sketching this out since I can't find the directrixes. If anyone could help with that and explain how to do the pole taken to be the leftmost focus that would be awesome!
 

Related to Finding Directrix and Sketching Hyperbola in Polar Coordinates

1. What are conic polar equations?

Conic polar equations are equations that represent conic sections (such as circles, ellipses, parabolas, and hyperbolas) in polar coordinates. They are written in the form of r = f(θ) where r is the distance from the origin and θ is the angle from the positive x-axis.

2. How are conic polar equations different from conic cartesian equations?

Conic polar equations use polar coordinates, which are based on distance and angle, while conic cartesian equations use rectangular coordinates, which are based on x and y coordinates. In polar equations, the focus is on the distance from the origin, while in cartesian equations, the focus is on the x and y coordinates.

3. What are the advantages of using conic polar equations?

Conic polar equations can be useful in situations where the focus is on the distance and angle from the origin, such as in engineering and physics applications. They can also simplify certain mathematical calculations, such as finding the area of a sector in a circle.

4. What are some common applications of conic polar equations?

Conic polar equations have many real-world applications, including mapping celestial bodies, designing satellite orbits, and creating lenses for telescopes and cameras. They are also used in engineering applications, such as designing curved structures and calculating the trajectory of projectiles.

5. How can I convert between conic polar and cartesian equations?

To convert from a conic polar equation to a cartesian equation, use the following formulas:
x = r cos(θ) and y = r sin(θ)
To convert from a cartesian equation to a conic polar equation, use the following formulas:
r = sqrt(x^2 + y^2) and θ = arctan(y/x)

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