Update 1.1.md

C01-The-Role-of-Algorithms-in-Computing/1.1.md

@@ -4,7 +4,7 @@ Give a real-world example in which one of the following computational problems a
 
 ### `Answer`
 * 用到排序的应用很多，比如电商网站对商品按价格进行排序
-* 关于矩阵相乘，我们需要找到最优的运算次数最少的运算次序，矩阵相乘在人工智能上用到很多
+* The multiplication process in computers are time consuming than addition process. If we have three or more matrices to multiply, then we should check the order in which to multiply to reduce the number of multiplications.
 * [From Wiki]The problem of finding convex hulls finds its practical applications in pattern recognition, image processing, statistics, geographic information system, game theory, construction of phase diagrams, and static code analysis by abstract interpretation. It also serves as a tool, a building block for a number of other computational-geometric algorithms such as the rotating calipers method for computing the width and diameter of a point set. also application in [CV](http://docs.opencv.org/doc/tutorials/imgproc/shapedescriptors/hull/hull.html).