回答: #DY / DX = 3sqrtx# 说明: #Y = 2xsqrtx = UV# #DY / DX = U(DV)/ DX + V(DU)/ DX# #U = 2X# #(DU)/ DX)= 2# #V = sqrtx = X ^(1/2)# #(DV)/(DX)= 1/2 * X ^(1 / 2-1)= X ^( - 1/2)/ 2# #DY / DX = 2×* X ^( - 1/2)/ 2 + 2 *的x ^(1/2)= sqrtx + 2sqrtx = 3sqrtx#