随笔分类 -  math

摘要：The Simple Arithmetic Sequences Let's say we have the simplest of arithmetic sequences. $\{1, 2, 3, \cdot\cdot\cdot, n\}$ And what I want to think abo 阅读全文

摘要：We know that: a = first termr = common ration = number of terms We'r going to use a notation $S_n$ to denote the sum of first n terms as following: $S 阅读全文

摘要：Quadratic Formula: The quadratic equation is as follows: $ax^2+bx+c=0$ The quadratic formula tells us that the solutions to this equation is $x = \fra 阅读全文