\(\operatorname{Cost}\left(h_{\theta}\left(x_{i}\right), y_{i}\right)=\left\{\begin{array}{c}-\log \left(h_{\theta}\left(x_{i}\right)\right), \text { if } y_{i}=1 \\ -\log \left(1-h_{\theta}\left(x_{i}\right)\right), \text { if } y_{i}=0\end{array}\right\}\)