Carlson symmetric elliptic integral of the second kind R_D
CarlsonRD[x, y, z]
CarlsonRD[2., 3., 5.]
→ 0.1332110927820146Plot[Table[CarlsonRD[3, y, z], {y, {1 / 2, 2, 5}}]//Evaluate, {z, 0, 10}, PlotLegends -> "Expressions"]
→ -Graphics-CarlsonRD[x, x, x]
→ x^(-3/2)