@@ -50,8 +50,27 @@ $$
点乘的运算
-- 2D: $\vec{a} \cdot \vec{b} = (^{x_a} _{y_a}) \cdot (^{x_b} _{y_b}) = x_a*x_b + y_a*y_b $
-- 3D: $\vec{a} \cdot \vec{b} = \begin{pmatrix}x_a \\ y_a \\ z_a\end{pmatrix} \cdot \begin{pmatrix} x_b \\ y_b \\ y_c \end{pmatrix} = x_a * x_b + y_a * y_b + z_a * z_b $
+- 2D:
+
+$
+\vec{a} \cdot \vec{b} =
+(^{x_a} _{y_a})
+\cdot
+(^{x_b} _{y_b})
+= x_a*x_b + y_a*y_b
+- 3D:
+\begin{pmatrix}
+x_a \\ y_a \\ z_a\
+end{pmatrix}
+\begin{pmatrix} x_b \\ y_b \\ y_c \end{pmatrix}
+= x_a * x_b + y_a * y_b + z_a * z_b
