Convert Rectangular to Polar: Solving for $\theta$

[karush]

Covert to polar
$$y=3 x$$
I got... But it didn't plot on desmos... Can't show polar graph here?
$$r\sin\left({\theta}\right)=3r\cos\left({\theta}\right)$$

 

[Ackbach]

Covert to polar
$$y=3 x$$
I got... But it didn't plot on desmos... Can't show polar graph here?
$$r\sin\left({\theta}\right)=3r\cos\left({\theta}\right)$$

Simplifying further:
$$\sin(\theta)=3 \cos(\theta) \quad \implies \quad \tan(\theta)=3\quad\implies\quad \theta=\arctan(3).$$
Alas, it appears that Desmos cannot plot $\theta$ as a function of anything, yet.

 

[karush]

OK, however desmos does plot

$$r=-2-3\sin\left({\theta}\right)$$

Although there is no way to put in $\theta$ on the drop down here

 

[Ackbach]

Hmm, let's see:

[desmos="-10,10,-10,10"]r=-2-3 sin(θ)[/desmos]

If you show the keyboard, then click the ABC on the lower left, you'll see a $\theta$ key. Interestingly, because I just typeset $\theta$ using the $\LaTeX$ code

$\theta$

I can copy that $\theta$ character and paste it into Desmos, and it understands it.

 

[karush]

I tried but the keyboard would not appear hiting the icon off the interactive tab.

It may be because I am using a android tablet, I have a lot of problems with the finger zoom also, the taptalk ad enlarges so much that's all you can see

 

[Ackbach]

I tried but the keyboard would not appear hiting the icon off the interactive tab.

It may be because I am using a android tablet, I have a lot of problems with the finger zoom also, the taptalk ad enlarges so much that's all you can see

Yeah, you're probably better off on a laptop or desktop. Still, we'd like our Tapatalk version to work ok, if possible.