@phi can you help on one more?
Eliminate the parameter.

x = 3 cos t, y = 3 sin t

Question

@phi can you help on one more?
Eliminate the parameter.

x = 3 cos t, y = 3 sin t

phi · Answer

I would square both equations

phi · Answer

and try to use cos^2 + sin^2 = 1  to get rid of the sin and cos

sleepyjess · Answer

Oh gosh, this goes back to trig identities doesn't it?

phi · Answer

yes, when you see trig functions, expect to use trig identities.
but if you use polar coords, you get use to the idea that r^2 = x^2 + y^2
and x = r cos theta  , y = r sin theta
If that does not make sense, ignore it.

sleepyjess · Answer

$x = 3 cos t\y = 3 sin t$

$x^2 = 9 cos^2 t\y^2 = 9 sin^2 t$

$x^2/9 = cos^2t\y^2/9 = sin^2t$

$(x/3)^2 + (y/3)^2 = 1$

phi · Answer

yes.  because that is the equation of a circle, the standard way is to write it
x^2 + y^2 = 9

sleepyjess · Answer

So is that it?

phi · Answer

your way is fine, but you might see it as I posted it.

sleepyjess · Answer

Ok :) Thank you!