#custom-activation

A tiny network has one input $y_i = 1$, a hidden unit with transfer function $x^3$ and an output unit with transfer function $\sin(2x)$: $\mathrm{net}_j = w_{ij} y_i$, $y_j = \mathrm{net}_j^3$, $\mathrm{net}_k = w_{jk} y_j$, $y_k = \sin(2\,\mathrm{net}_k)$, and the loss is $E = \tfrac12 (y_k - d)^2$ with target $d = 0$. For $w_{ij} = 0.5$ and $w_{jk} = 2$, what is $\partial E / \partial w_{ij}$? Round to 3 decimals.