D3.7. In each of the following parts, find a numerical value for div D at the point specified: (a) D = (2xyz – y²)a, + (x²z – 2xy)a, + x²ya.C/m² at PA(2, 3, –1); (b) D = 2pz² sin² p a, + pz² sin 2p as...

Extracted text: D3.7. In each of the following parts, find a numerical value for div D at the point specified: (a) D = (2xyz – y²)a, + (x²z – 2xy)a, + x²ya.C/m² at PA(2, 3, –1); (b) D = 2pz² sin² p a, + pz² sin 2p as + 2p²z sin² PB(p = 2, ¢ = 110°, z = –1); (c) D = 2r sin 0 cos ø a, +r cos 0 cos o ag – r sin ø a, C/m² at Pc(r = 1.5, 0 = 30°, ø = 50°). p a_C/m² at - Ans. –10.00; 9.06; 1.29