Derive $\sec^{-1}\bigg(\large\frac{1}{2x^2-1}\bigg)$ with respect to $\sqrt {1+3x}$ at $x=-\large\frac{1}{3}$:

Question

\[(a)\;does\;not\;exit \quad (b)\;\frac{1}{2} \quad (c)\;\frac{1}{3} \quad (d)\;none\;of\;these\]