]> $$\begin{array}{rcl}Bi\prime \left(0\right)& =& \frac{3^{\frac{1}{6}}}{\Gamma \left(\frac{1}{3}\right)}\\ Bi\prime \left(z\right)& =& \frac{z}{\sqrt{3}}\left(I_{\frac{2}{3}}\left(\zeta \right)+I_{-\frac{2}{3}}\left(\zeta \right)\right)& ;& \zeta =\frac{2}{3}{z}^{\frac{2}{3}}\\ Bi\prime \left(-z\right)& =& \frac{z}{\sqrt{3}}\left(J_{-\frac{2}{3}}\left(\zeta \right)+J_{\frac{2}{3}}\left(\zeta \right)\right)\end{array}$$