作者gs9706 (神手)
看板trans_math
标题Re: [考古] 95年中正 通讯
时间Sun Jul 5 20:46:18 2009
※ 引述《egg790724 (鸡蛋)》之铭言:
: (9)Integrate f(x,y,z)=x-3y^2+z over the line segment X
: joining the point (1,1,0) to the point (1,1,1).
: (11)Find the circulation of the field F(x,y,z)=(x^2-y)i+4zj+x^2k
: around the curve C in which the plane z=2 meets the cone z=(x^2+y^2)^1/2
: counterclockwise as viewed from above.
: 这两题不知道怎麽下手@@
: 请各位高手帮忙一下
: 谢谢~
(9)r(t)= i + j + tk
dr/dt=k=v(t) |v(t)|=1
线积分公式:∫f(t) |v(t)| dt (0<=t<=1)
(10)F(x,y,z)=Mi+Nj+Pk
circulation=∫Mdx+Ndy+Pdz
z=2 与 z=(x^2+y^2)^1/2 交於一个(x^2+y^2)=4的圆轨迹
公式带入得解
PS:不负责任随便解.....
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※ 编辑: gs9706 来自: 219.86.81.192 (07/05 20:47)