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Parametric equations question

I’m finding a Cartesian equation for the parametric equations of

X=t^3, y=2(t^2)
Normally I would just eliminate t from x and sub into y but I remember my teacher saying never to take square/cube roots when doing parametrics as you’d lose solutions

What would I do in this case?
You teacher gave you an advice because it gives complicated equation. You still can do that.
Reply 2
Original post by Hammad(214508)
T is also x/3, from the first equation. And complicated equation. You still can do that.


T is being raised to the power of 3 though, I can’t simply divide by 3...
Original post by ElDonCorleone
T is being raised to the power of 3 though, I can’t simply divide by 3...

yeah sorry, I miss read it, but in this case you will have to root one of the equations. Your teacher probably said don't do it if there is other option, because rooting gives complicated equations
Original post by ElDonCorleone
I’m finding a Cartesian equation for the parametric equations of

X=t^3, y=2(t^2)
Normally I would just eliminate t from x and sub into y but I remember my teacher saying never to take square/cube roots when doing parametrics as you’d lose solutions

What would I do in this case?


There's nothing wrong with taking roots as long as you're consistent. Here, taking a square root will introduce you to ±y2\pm \sqrt{\frac{y}{2}} but if you consider the fact that any odd root doesn't introduce this ±\pm business, then taking the cube root of xx is the way to go to get tt
(edited 6 years ago)
Reply 5
Original post by RDKGames
There's nothing wrong with taking roots as long as you're consistent. Here, taking a square root will introduce you to ±y2\pm \sqrt{\frac{y}{2}} but if you consider the fact that any odd root doesn't introduce this ±\pm business, then taking the cube root of xx is the way to go to get tt


So my answer is simply 2x^2/3 ?
Original post by ElDonCorleone
So my answer is simply 2x^2/3 ?


Yes.
Reply 7
Original post by RDKGames
Yes.


Thanks!

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