31.03.2019 Views

Exercicios resolvidos James Stewart vol. 2 7ª ed - ingles

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

272 0 CHAPTER 15 MULTIPLE INTEGRALS<br />

Therefore<br />

E = { (x y z) 1 -2 < x < 2 0 < y < 4 ·_ x 2 - 1 yl 4 - :z;2 - y < z < 1 yl 4 - :z;Z - y }<br />

, , - -'-- , 2 - - 2<br />

= { (x, y,z) I 0:::; y:::; 4, - y'4""='1j:::; x:::; y'4""='1j, - h/4 - x 2 - y:::; z ~ ~yf4- x 2 - y}<br />

= { (x,y,z) I -1 $ z 5: 1, 0 5: y 5:4 - 4z 2 , - yf4 - y- 4z 2 :::; x:::; yf4 - y - 4z 2 }<br />

= { (x, y, z) I 0 5: y 5: 4, - ty'4""='1j $ z $ ty'4""='1j, - j4-y- 4z 2 :::; x:::; yf4 - y- 4z 2 }<br />

Then<br />

= { ( x, y, z) I - 2 5: x 5: 2, - ~ J 4 - x 2 :::; z :::; t J 4 - x~, 0 :::; y :::; 4 - :z: 2 - 4z 2 }<br />

= { (x, y, z) I -1 5: z 5: 1, - .J4 - 4z 2 :::; x:::; .J4- 4z 2 , 0:::; y:::; 4- x 2 - 4z 2 }<br />

Iff sf ( x,y,z ) dV = !_ 2 ; -~/ 0 2 / x,y,z dzdydx=:Jo --14-ii -~ 1 2<br />

2 r4-x2 JJ4-x2-yf2 ( ) r4 f-14-ii JJ4-:z:2-yj 2 ( )<br />

! x,y,z dzdxdy<br />

I I f4- 4z2 JV4-y-4z2 ( ) , f4 f-/4-!i/2 J V4-y-4z 2 (<br />

= - tJo -.J _ _ z 4 11 4 2 f x, y, z dx dy dz = Jo --14-ii/ 2 - J _ _ : 4 11 4 2 f x, y, z) dx dz dy<br />

f 2 J~/2 r4-x2 -4:2' . ) fl J J4- 4:;2 r4-o: 2 -4: 2 ( )<br />

= _ 2<br />

r;--:; Jo f(x,y,z dydzdx= _ 1 ~Jo f x,y,z dydxdz<br />

-y4- :z:2/2<br />

-y4-4z2<br />

31 .<br />

y<br />

(- 2,4,0;<br />

JC<br />

(2,4,0)<br />

X<br />

4 y - 2 2 JC<br />

If D1, Dz, and Da are the projections of Eon the xy-, yz-, and xz-planes, then<br />

D1 = { (x, y) I -2 $ x 5: 2, :z: 2 ~ y 5: 4} = { (x, y) I 0 :::; y :::; 4, -y'Y $ x:::; vY },<br />

D2 = { (y,z) I 0 :::; y $ ,4, 0 :::; z 5: 2- ~y } = { (y,'z) I 0:::; z 5: 2,0 ~ y:::; 4 -<br />

2z}, and<br />

Ds = { (x, z) I - 2 $ x :::; 2, 0 5: z ~ 2 - ~~ 2 } = { (x, z) I 0 :::; i ~ 2, - .J4- 2z :::;. x $ v'4 - 2z}<br />

® 2012 Cenaoge Lcoming. All Rigbu Rcsem:d. May not be sconn<strong>ed</strong>, copi<strong>ed</strong>, or duplicat<strong>ed</strong>, or post<strong>ed</strong> to a publicly aeccssiblc website, In whole or in port.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!