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View Full Version : R^2 = 8/(2-sin^2 θ) Convert to rectangular form?


Jurrasic
Oct2-11, 03:11 PM
Is it right to multiply everything on both sides first, by the (2-sin^2 θ) ? Why would you want to do that? In terms of how it should look, and what variable to solve for, what exactly is the goal here and why?

vela
Oct2-11, 03:31 PM
Yes, you can do that. When converting to rectangular form, you want to get each sine and cosine multiplied by R because x=R cos θ and y=R sin θ. (I'm assuming you're working with polar coordinates here.) Here you have sin2 θ, so you want it multiplied by R2, one factor of R for each sine.

eumyang
Oct2-11, 06:06 PM
In terms of how it should look, and what variable to solve for, what exactly is the goal here and why?
You don't necessarily solve for a variable. The goal is to rewrite the equation so that the variables are x's and y's, not r's and θ's. After multiplying both sides by the denominator, add sin2 θ to both sides, and then use the equations that vela gave you. (They are the same one's I mentioned in your previous thread.)