표면 적분 (2x+z) dydz+zdxdy 적분 영역: z=x^2+y^2(0

표면 적분 (2x+z) dydz+zdxdy 적분 영역: z=x^2+y^2(0

원식=ᄉ((2x+z)cosA+zcosC)dS=ᄃ((2x+z)cosA/|cosC|+z*cosC/|cosC|)dxdy 평면법 벡터={-2x,-2y,1}cosA=-2x*(1+4x^2+4y^2)^(-1/2)cosC=1*(1+4x^2+4y^2)^(-1/2)그래서:cosA/|cosC