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Homework Help: 3 curve integral (asap)

  1. Nov 27, 2013 #1
    Find region between these 3 curves.
    2y=4sqrt(x)
    y=5
    2y+2x=6

    Not sure how to find limits or actually setup the intigration.. is it just (left-mid-right?) But no idea for limits..
     
  2. jcsd
  3. Nov 27, 2013 #2

    SteamKing

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    Staff Emeritus
    Science Advisor
    Homework Helper

    When in doubt, make a sketch of the three curves (actually, one curve and two lines) and see what drops out.
     
  4. Nov 27, 2013 #3
    Hmm, I tried that and got a somewhat triangle, broke it up and got 2 integrals..
    From -2 to 1
    (5-(3-x))

    From 1 to 6
    5-2sqrt(x)

    But it was wrong
     
  5. Nov 27, 2013 #4

    Mark44

    Staff: Mentor

    You should simplify the 1st and 3rd equations.
    y = 2√x
    y + x = 3

    There's no point in leaving in those common factors.

    Yes. You have the x coordinates for two of the intersection points correct, but the square root function and the horizontal line don't intersect for x = 6.

    Try again.
     
  6. Nov 27, 2013 #5

    lurflurf

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    Homework Helper

    almost
    From -2 to 1
    (5-(3-x))

    From 1 to (try again)
    5-2sqrt(x)
    $$\mathrm{Area}=\int_{-2}^1 \! (5-(3-x))\, \mathrm{d}x+\int_1^{\text{try again}} \! (5-2\sqrt{x}) \, \mathrm{d}x$$
     
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