Double integrals First, let's recall Riemann sums for integrals - - PDF document

double integrals first let s recall riemann sums for
SMART_READER_LITE
LIVE PREVIEW

Double integrals First, let's recall Riemann sums for integrals - - PDF document

Double integrals First, let's recall Riemann sums for integrals with a single variable... 1 2 3 4 5 Some comments: (1) Note that we can estimate double integrals using double Riemann sums. While this is tedious by hand, computers do this


slide-1
SLIDE 1

1

Double integrals First, let's recall Riemann sums for integrals with a single variable...

slide-2
SLIDE 2

2

slide-3
SLIDE 3

3

slide-4
SLIDE 4

4

slide-5
SLIDE 5

5

slide-6
SLIDE 6

6

Some comments: (1) Note that we can estimate double integrals using double Riemann sums. While this is tedious by hand, computers do this type of thing routinely. (2) The interpretation as volume is only for surfaces f(x,y)>0; otherwise we get regions with "negative" volume. Volume calculation is not the motivation anyway, just a way to start thinking about the Riemann sum.

slide-7
SLIDE 7

7

Midpoint rule: Use the centers of rectangles as sample points in the double Riemann sum.

slide-8
SLIDE 8

8

slide-9
SLIDE 9

9

Average value

slide-10
SLIDE 10

10

Calculation of integrals: iterated integrals.

slide-11
SLIDE 11

11

slide-12
SLIDE 12

12

slide-13
SLIDE 13

13

Fubini's Theorem *So you can switch the order of integration for convenience... very useful sometimes. *Here f(x,y) can be discontinuous on a finite set of curves so long as it is also bounded and the iterated integrals exist.

slide-14
SLIDE 14

14

slide-15
SLIDE 15

15

slide-16
SLIDE 16

16

Practice!

slide-17
SLIDE 17

17

slide-18
SLIDE 18

18

slide-19
SLIDE 19

19