[微積] 97交大微積分

看板Math作者 (dayeh)時間13年前 (2011/02/06 16:30), 編輯推噓4(405)
留言9則, 4人參與, 最新討論串1/1
1.Find the area of the region D ,which is the part of the plane x+2y+z=4 that lies inside the cyliner by x^2+y^2=4 2.Find the maximum and minimum values of the fuction f(x y z)=x^2+y^2+z^2 on the region described by inequality x^4+y^4+z^4 <= 1 想請問這兩題怎麼算?謝謝 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 61.216.112.207

02/06 19:04, , 1F
不會算 謝謝
02/06 19:04, 1F

02/06 20:38, , 2F
第二題直覺用Lagrange multipliers不過我也忘記怎用
02/06 20:38, 2F

02/06 20:58, , 3F
沒記錯面和圓柱截面是橢圓 z=4-x-2y 用科西求出z極值
02/06 20:58, 3F

02/06 21:00, , 4F
z的差和圓柱直徑求出橢圓長軸 短軸等於圓柱的直徑
02/06 21:00, 4F

02/06 21:00, , 5F
再代πab 不知道這樣算對不對
02/06 21:00, 5F

02/06 22:13, , 6F
第二題先用偏導數=0求出來的點看有沒有落在範圍裡面
02/06 22:13, 6F

02/06 22:13, , 7F
邊界的值在用lagrange
02/06 22:13, 7F

02/06 22:31, , 8F
喔喔
02/06 22:31, 8F

02/06 23:36, , 9F
第一題重積分
02/06 23:36, 9F
文章代碼(AID): #1DJbmbqV (Math)