Please help me.?
回答 (1)
2015-11-15 12:31 am
1st do the sketch..let z = 0 { xy plane } and sketch 3x + 4y = 12 ;
then let x = 0 { yz plane } and sketch the line , finally let y = 0 { x z plane }
and sketch the line { all in the 1st octant ! }...
then dz is z in [ 0 , 12 - 3x - 4y ] , dy in [ 0 , 12 - 3x ] ,
finally dx in [ 0 , 4]...same concepts for the other two integrals
then let x = 0 { yz plane } and sketch the line , finally let y = 0 { x z plane }
and sketch the line { all in the 1st octant ! }...
then dz is z in [ 0 , 12 - 3x - 4y ] , dy in [ 0 , 12 - 3x ] ,
finally dx in [ 0 , 4]...same concepts for the other two integrals
收錄日期: 2021-04-21 15:02:08
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20151114161957AA6a1Sh