update chapter11

docs/chapter11/chapter11.md

@@ -292,12 +292,12 @@ $$
 \begin{aligned}
 \sum_{j=1}^{k}\boldsymbol b_{\boldsymbol j}\boldsymbol \alpha ^{\boldsymbol j} 
 & = \sum_{j=1}^{k}\left (\begin{bmatrix}
-b_{1}^{j}\\ b_{w}^{j}
+b_{j}^{1}\\ b_{j}^{2}
 \\ \cdot 
 \\ \cdot 
 \\ \cdot 
-\\ b_{d}^{j}
-\end{bmatrix}\cdot 
+\\ b_{j}^{d}
+\end{bmatrix}`\cdot 
 \begin{bmatrix}
  \alpha _{1}^{j}& \alpha _{2}^{j} & \cdot  & \cdot  & \cdot  & \alpha _{m}^{j}
 \end{bmatrix} \right )\\