Convert the polar equation to rectangular form.

Lebombo
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Homework Statement



r = 3sin\theta

since

x= rcos\theta

x = 3sin\thetacos\theta

and since:

y = rsin\theta

y = 3sin^2\theta


Then I'm sort of stuck..
 
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Lebombo said:

Homework Statement



r = 3sin\theta

since

x= rcos\theta

x = 3sin\thetacos\theta

and since:

y = rsin\theta

y = 3sin^2\theta


Then I'm sort of stuck..

You are making it way too difficult. Put ##\sin\theta =\frac y r## in your first equation then see if you can get an xy equation from that.
 
Lebombo said:

Homework Statement



r = 3sin\theta

since

x= rcos\theta

x = 3sin\thetacos\theta

and since:

y = rsin\theta

y = 3sin^2\theta


Then I'm sort of stuck..

Try putting sinθ=y/r.
 
LCKurtz said:
You are making it way too difficult. Put ##\sin\theta =\frac y r## in your first equation then see if you can get an xy equation from that.


Like so:

r = 3sinθ becomes (r=3\frac{y}{r})

= (r =\sqrt{3y}) ?


or solving for y, (y = \frac{r^2}{3})



or do you mean something like this:



(\frac{y}{r} = sinθ) becomes (\frac{y}{3sinθ} = sinθ)


= (y = 3sin^{2}θ)
 
Lebombo said:
Like so:

r = 3sinθ becomes (r=3\frac{y}{r})

= (r =\sqrt{3y}) ?or solving for y, (y = \frac{r^2}{3})
or do you mean something like this:
(\frac{y}{r} = sinθ) becomes (\frac{y}{3sinθ} = sinθ)= (y = 3sin^{2}θ)

You also want to use ##r^2=x^2+y^2##. You need to express both ##sin(\theta)## and r in terms of x and y. Try once more.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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