Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

Integration for volume of elliptical parabaloid?

solve for volume under the elliptical paraboloid z=2x^2+6y^2 and over the rectangle R=[−5,5]x[−2,2].

(its the rectangle part thats really confusing me, I get 296/3)

Update:

so shouldnt it just be:

int (2x^2 + 6y^2) dxdy, x=-5 to -2, y=2 to 5? Because that answer is wrong...

2 Answers

Relevance
  • 1 decade ago
    Favorite Answer

    Regarding your additional details:

    No. By definition of the cartesian product of two sets,

    [-5,5]x[-2,2] = { (x,y) | -5<=x<=5 and -2<=y<=2 },

    (where "<=" means "less than or equal to".)

    What do you think that the answer is?

    There are sometimes errors in the back of the book...

    I came up with 2960/3, so either you have a typo above, or one of us made an arithmetic error... For the rectangle part: The [-5,5] says that x ranges from -5 to 5, and the [-2,2] says that y ranges from -2 to 2. You can set your iterated integral as a dydx integral or as a dxdy integral. If you use dydx, then the "inner" integral sign is the one with -2 and 2 (the y's), and the "outer" integral sign is the one with the -5 and 5 (the x's). For the dydx integral, they switch. Either order should give the same result by Fubini's theorem.

  • 1 decade ago

    The rectangle defines the limits of integration for the triple integral.

Still have questions? Get your answers by asking now.