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parametric circles and why I'm an arse watch

1. I often spend lots of time on pratice exam papers working out the areas enclosed by

x=asint
y=bcost

no-one ever told me that the area of an ellipse with radii (r1) and (r2) = pi(r1)(r2). This sshould ssave so much time in P3 if it comess up.

MB
2. (Original post by musicboy)
I often spend lots of time on pratice exam papers working out the areas enclosed by

x=asint
y=bcost

no-one ever told me that the area of an ellipse with radii (r1) and (r2) = pi(r1)(r2). This sshould ssave so much time in P3 if it comess up.

MB
you'll almost certainly be told to use integration to find the area, otherwise its too easy
3. (Original post by It'sPhil...)
you'll almost certainly be told to use integration to find the area, otherwise its too easy
damn!!! At least it is a good way to check my answer.

MB
4. Oh yeah, and if they forget to write "by integration" then i'm using my method.

MB
5. (Original post by musicboy)
I often spend lots of time on pratice exam papers working out the areas enclosed by

x=asint
y=bcost

no-one ever told me that the area of an ellipse with radii (r1) and (r2) = pi(r1)(r2). This sshould ssave so much time in P3 if it comess up.

MB
ooh! i didnt know that! Cheers.. yeah, like you said, good way of checking answer.
6. (Original post by musicboy)
I often spend lots of time on pratice exam papers working out the areas enclosed by

x=asint
y=bcost

no-one ever told me that the area of an ellipse with radii (r1) and (r2) = pi(r1)(r2). This sshould ssave so much time in P3 if it comess up.

MB
Ohhh didn't actually know that, does that mean that if we are given something like....

x = 4cost
y= 6sint

Then the area would be given by (3)(2)pi???
7. (Original post by Leekey)
Ohhh didn't actually know that, does that mean that if we are given something like....

x = 4cost
y= 6sint

Then the area would be given by (3)(2)pi???
wouldnt it be (4)(6)pi?
8. (Original post by kimoni)
wouldnt it be (4)(6)pi?
Ahh yes sorry, I typed out the equations and the proposed answer and then decided to change them for slightly more intersting numbers....*doh*

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Updated: June 8, 2004
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