Quantcast

Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

agentx5 Group Title

Yikes, need to find the area and the name for these parametric equations: x(t) = a cos(t) (2 cos(2 t)+1) y(t) = a sin(t) (2 cos(2 t)+1) What is...? I don't even...? How? I'll draw the graph....

  • 2 years ago
  • 2 years ago

  • This Question is Closed
  1. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Cartesian? Check me please? x^6+3 x^4 (y^2-3)+3 x^2 y^2 (y^2+2)+y^6 = y^4 |dw:1342133559037:dw|

    • 2 years ago
  2. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    It looks like of like a D-orbital from chemistry, but it's got little lobes on the vertical, so that means it's probably more like some weird F-orbital. :-D Help?

    • 2 years ago
  3. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    \[x^6+3 x^4 (y^2-3)+3 x^2 y^2 (y^2+2)+y^6 = y^4\]

    • 2 years ago
  4. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    I just chose some arbitrary "a" constant to sub.

    • 2 years ago
  5. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342133866479:dw|

    • 2 years ago
  6. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Is that \(\tan t\) @mahmit2012 ? Ty in advance btw, you always seem to be the one who's here to help when I get stuck on these challenge problems :D

    • 2 years ago
  7. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342133990522:dw|

    • 2 years ago
  8. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342134107025:dw|

    • 2 years ago
  9. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342134151837:dw|

    • 2 years ago
  10. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    \(x^2 + y^2 = \text{radius}^2\)

    • 2 years ago
  11. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342134219662:dw|

    • 2 years ago
  12. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    so a=1

    • 2 years ago
  13. asnaseer Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    you can see a graph of this using wolfram, e.g.: http://www.wolframalpha.com/input/?i=plot+%7Bx%3Da*cos%28t%29%282cos%282t%29%2B1%29%2C+y%3Da*sin%28t%29%282cos%282t%29%2B1%29%7D+when+a%3D3 your graph is correct :)

    • 2 years ago
  14. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    \(\text{Area} = 3 \pi a^2\), correct ?

    • 2 years ago
  15. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Whoa cool link there, @asnaseer I didn't know you could do that with Wolfram, that's some pretty fancy syntax :D

    • 2 years ago
  16. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Does this graph actually have a name though? It's not as if I can just Google the image lol

    • 2 years ago
  17. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342134548532:dw|

    • 2 years ago
  18. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342134699157:dw|

    • 2 years ago
  19. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342134862828:dw|

    • 2 years ago
  20. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342134931824:dw|

    • 2 years ago
  21. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    *reading & taking notes* :-3

    • 2 years ago
  22. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    origin build with 1+cos2t=0 _> x=0 , y=0 common term between x , y

    • 2 years ago
  23. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342135079515:dw|

    • 2 years ago
  24. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342135156538:dw|

    • 2 years ago
  25. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    is it clear?

    • 2 years ago
  26. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    for exactly drawing d/dt=0 for x , y give you some critical points

    • 2 years ago
  27. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Clear, you are finding the polar lines, basically, where r = 0.

    • 2 years ago
  28. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342135317896:dw|

    • 2 years ago
  29. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    We just touched on polar stuff today, this question was from the "challenge" section of the written homework. The other curves have names that we discussed in the lecture like "carotid", "ellipse", and "circle" which are kind of obvious which is which.

    • 2 years ago
  30. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Yep! That looks like the other questions where we were asked to find the vertical and horizontal tangents

    • 2 years ago
  31. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    dy/dt = 0 is for horizontal I believe

    • 2 years ago
  32. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342135476935:dw|

    • 2 years ago
  33. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342135505524:dw|

    • 2 years ago
  34. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    interesting problem !

    • 2 years ago
  35. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Does this funky thing have a name though? :-D

    • 2 years ago
  36. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    No! it has a nice shape .

    • 2 years ago
  37. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    It just asks me to type in the "area" in the one text field. Which was correct yay! And then it has a text box under it for "name of curve". The others were easy, but this one I haven't got a clue. Maybe it's in the text, somewhere amidst all its pages but it's not easy to find.

    • 2 years ago
  38. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    It kind of looks like... one of those things when you roll a circle within a circle

    • 2 years ago
  39. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    Try to solve one by yourself then think it's so easy and sure after that enjoy with the figure.

    • 2 years ago
  40. agentx5 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Well I'm not going to sweat it, the hard part is done. Who cares about the name, you're right :-D

    • 2 years ago
  41. mahmit2012 Group Title
    Best Response
    You've already chosen the best response.
    Medals 4

    |dw:1342136059673:dw|

    • 2 years ago