(a) The function u satisfies V2u = 0 in the volume V and u = 0 on S, the surface bounding V. Show that u = 0 everywhere in V. The function u satisfies V = 0 in V and v is specified on S. Show that for all functions w such that w = v on S Do Vv. VwdV = v dv. Hence show that wdV = {\v + 1 (w_v) }dV > \\v dv. (b) The function satisfies V2 = p(x) in the spherical region |x|