作者midarmyman (midarmyman)
看板trans_math
标题Re: [积分] 一题线积分
时间Fri Jun 11 20:23:18 2010
※ 引述《retryi12 (WOW)》之铭言:
: Calculate ∫∫(x^3dydz+y^3dzdx+z^3dxdy)
: S
: where S is a surface determined by x^2+y^2+z^2=a^2
: 因为用高斯散度定理
: 我搞不清楚∫∫F˙ndS 的F怎麽拆开~
: 谢谢~
Gauss's divergence theorem
∫∫F‧n dS = ∫∫∫divF dV
div(x^3,y^3,z^3)=3(x^2+y^2+z^2)
3∫∫∫x^2+y^2+z^2dxdydz
2pi pi/0 a
=3 ∫ ∫ ∫ ρ^4 sinψ dρdψdθ
0 0 0
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※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 140.117.198.78
1F:推 Frobenius:a^5 (12π/5) 118.161.248.74 06/11 20:53
2F:→ midarmyman:最近学到级数解 发现你ID好酷XD 140.117.198.78 06/11 21:34
3F:推 retryi12:谢拉我之前把微面积dS搞错了~ 58.99.62.99 06/12 18:37