모두CBT
전계 E의 x, y, z 성분을 Ex, Ey, Ez라 할 때 divE는?
∂Ex∂x+∂Ey∂y+∂Ez∂z\dfrac{\partial E_x}{\partial x}+\dfrac{\partial E_y}{\partial y}+\dfrac{\partial E_z}{\partial z}∂x∂Ex+∂y∂Ey+∂z∂Ez
i∂Ex∂x+j∂Ey∂y+k∂Ez∂zi\dfrac{\partial E_x}{\partial x}+j\dfrac{\partial E_y}{\partial y}+k\dfrac{\partial E_z}{\partial z}i∂x∂Ex+j∂y∂Ey+k∂z∂Ez
∂2Ex∂x2+∂2Ey∂y2+∂2Ez∂z2\dfrac{\partial^2E_x}{\partial x^2}+\dfrac{\partial^2E_y}{\partial y^2}+\dfrac{\partial^2E_z}{\partial z^2}∂x2∂2Ex+∂y2∂2Ey+∂z2∂2Ez
i∂2Ex∂x2+j∂2Ey∂y2+k∂2Ez∂z2i\dfrac{\partial^2 E_x}{\partial x^2}+j\dfrac{\partial^2 E_y}{\partial y^2}+k\dfrac{\partial^2 E_z}{\partial z^2}i∂x2∂2Ex+j∂y2∂2Ey+k∂z2∂2Ez