모두CBT
점전하에 의한 전위 함수가 V=1x2+y2[V]V = \dfrac{1}{x^2+y^2}[V]V=x2+y21[V]일 때 gradV는?
−ix+jy(x2+y2)2-\dfrac{ix+jy}{(x^2+y^2)^2}−(x2+y2)2ix+jy
−i2x+j2y(x2+y2)2-\dfrac{i2x+j2y}{(x^2+y^2)^2}−(x2+y2)2i2x+j2y
−i2x(x2+y2)2-\dfrac{i2x}{(x^2+y^2)^2}−(x2+y2)2i2x
−j2y(x2+y2)2-\dfrac{j2y}{(x^2+y^2)^2}−(x2+y2)2j2y