diff --git a/CustomView/Advance/[9]Matrix_Basic.md b/CustomView/Advance/[9]Matrix_Basic.md
index e68cca8..2512ba8 100644
--- a/CustomView/Advance/[9]Matrix_Basic.md
+++ b/CustomView/Advance/[9]Matrix_Basic.md
@@ -122,7 +122,7 @@ Matrix 是一个矩阵，肯定会涉及到一些比较麻烦的理论知识，
 
 以点(10,10)为例，我们将x缩放到原来到0.5倍，y缩放到原来到2倍，我们可以轻易到算出结果:(10x0.5, 10x2) = (5, 20)
 
-矩阵计算公式:
+计算公式:
 
 ![](http://latex.codecogs.com/png.latex?
 $$
@@ -149,7 +149,7 @@ y
 $$)
 
 
-用计算示例:
+计算示例:
 
 ![](http://latex.codecogs.com/png.latex?
 $$
@@ -177,6 +177,38 @@ $$)
 
 #### b.错切
 
+计算公式:
+
+![](http://latex.codecogs.com/png.latex?
+$$
+\\left [ 
+\\begin{matrix} 
+X\\\\
+Y
+\\end{1} 
+\\right ] 
+ = 
+\\left [ 
+\\begin{matrix} 
+1 & Skew\\_X \\\\
+Skew\\_Y & 1 
+\\end{1} 
+\\right ] 
+ . 
+\\left [ 
+\\begin{matrix} 
+x\\\\
+y
+\\end{1} 
+\\right ]
+$$)
+
+```
+X = x + Skew_X * y
+Y = Skew_Y * x + y
+```
+
+计算示例: