Polar and cartesian coordinates

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SUMMARY

The discussion focuses on converting the polar equation r = 2/(3cos(theta) - 9sin(theta)) into Cartesian coordinates. The key steps involve multiplying both sides by (3cos(theta) - 9sin(theta)) to eliminate the fraction, leading to the equation r(3cos(theta) - 9sin(theta)) = 2. This transformation utilizes the relationships r = (x^2 + y^2)^(1/2), x = rcos(theta), and y = rsin(theta) to facilitate the conversion. The solution highlights the importance of recognizing algebraic manipulation in solving polar to Cartesian conversions.

PREREQUISITES
  • Understanding of polar coordinates and their equations
  • Familiarity with Cartesian coordinates and their equations
  • Knowledge of trigonometric identities, specifically sin^2(x) + cos^2(x) = 1
  • Basic algebraic manipulation skills
NEXT STEPS
  • Study the conversion process between polar and Cartesian coordinates in detail
  • Learn about graphing polar equations and their Cartesian equivalents
  • Explore advanced polar coordinate applications in calculus
  • Investigate the use of polar coordinates in physics, particularly in mechanics
USEFUL FOR

Students studying mathematics, particularly those focusing on coordinate systems, as well as educators teaching algebra and trigonometry concepts.

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Homework Statement


Write the following polar equation in Cartesian coordinates:
r= 2/(3cos(theta)-9sin(theta))


Homework Equations


r = (x^2 + y^2) ^.5
x=rcos theta
y=rsin theta
sin^2(x)+cos^2(x) = 1


The Attempt at a Solution


I'm stuck on how to do this. Any push in the right direction would be appreciated greatly!
 
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Clear that fraction by multiplying both sides by 3cos(theta)- 9sin(theta) to get
r(3cos(theta)- 9sin(theta))= 3 (r cos(theta))- 9(r sin(theta))= 2.

Now it should be obvious.
 
Wow, I can't believe that I didn't see that. Thanks a lot!
 

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