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    Just trying to get my head round how limits work on polar integration!
    Name:  lol.png
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    (Drawing isnt great!)

    But basically, if both the above were in polar form, so like the line is
    r = \frac{\pi}{2}
    and the curve was r = 4cos\theta
    (randomly made up)
    and the curve cut the axis at \pi

    To find the blue area, would the limits of
    \frac{1}{2} \displaystyle\int^\pi_\frac{\pi}  {2} (4cos\theta)^2\ d\theta
    give the blue area or blue and orange?
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    (Original post by NiceToMeetYou)
    Just trying to get my head round how limits work on polar integration!
    Name:  lol.png
Views: 65
Size:  4.7 KB
    (Drawing isnt great!)

    But basically, if both the above were in polar form, so like the line is
    r = \frac{\pi}{2}
    More like \theta=\frac{\pi}{4}

    and the curve was r = 4cos\theta
    (randomly made up)
    and the curve cut the axis at \pi
    At \pi/2 I think you mean

    To find the blue area, would the limits of
    \frac{1}{2} \displaystyle\int^\pi_\frac{\pi}  {2} (4cos\theta)^2\ d\theta
    give the blue area or blue and orange?
    \frac{1}{2} \displaystyle\int^\frac{\pi}{2}_  {\frac{\pi}{4}}(4cos\theta)^2\ d\theta

    gives the area in blue.
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    (Original post by ghostwalker)
    More like \theta=\frac{\pi}{4}



    At \pi/2 I think you mean



    \frac{1}{2} \displaystyle\int^\frac{\pi}{2}_  {\frac{\pi}{4}}(4cos\theta)^2\ d\theta

    gives the area in blue.
    Is there an explanation as to why, obviously with cartesian coordinates integrating between the axis and intersect would give blue and orange

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    (Original post by NiceToMeetYou)
    Is there an explanation as to why, obviously with cartesian coordinates integrating between the axis and intersect would give blue and orange

    Posted from TSR Mobile
    It should be in your textbook.

    The intgral gives the area defined by the two values of theta and from the origin to the curve.
 
 
 
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