implementa

1. (a+b-c)(a-b+c) =(a+(b-c))(a-(b-c)) 2. a()+b() remove parentheses and merge similar terms 3. Calculate the value of the independent variable of the function, such as f(1/3+1/6)+f(1/3-1/6)=f(1/3)f1/6), get f(1/2)+f(1/6)=f(1/3)f1/6 4. Move the terms of various equations together and combine the similar terms. 5. Calculate the value of the root 6. Calculate the value of the discrimination formula of the root 7. Simplify the result of simplified (a+b)^2 8. Simplify the result of multiplying same algebraic formula on both sides of the equation 9. Reduce the equations/inequalities generated by retaining intermediate calculation results 10. a/b>n>0, directly use the relevant properties of a/b>0, support n>a>=0, n>b>0 11. Add the equality u=(x+1)/(x-1) when making an introduction to the classification of log_a (x+1)/(x-1) > 1 12. Support f(f(x)) as the usage of replaceing unknown, so that t=f(x) 13. Input and execute, no need to click the selection again. 14. Provide a vertical list display of existing equations/inequalities 15. Click on the color topic to see the explanation of relevant concepts. 16. Other errors and bugs: iPad input interception, the operation does not match its interpretation, and the standard judgment of quadratic equations is not strict. 1. (a+b-c)(a-b+c) =(a+(b-c))(a-(b-c)) 2. a()+b()去括号并合并同类项 3. 计算函数自变量的值，例如f(1/3+1/6)+f(1/3-1/6)=f(1/3)f1/6),得f(1/2)+f(1/6)=f(1/3)f1/6 4. 对各类方程一并移项并合并同类项 5. 计算根的值 6. 计算根的判别式的值 7. 简化（a+b）^2的结果 8. 简化等式两边同乘代数式的结果 9. 减少保留中间计算结果产生的等式/不等式 10. a/b>n>0, 直接使用a/b>0 的相关性质，支持 n>a>=0, n>b>0 11. 对 log_a (x+1)/(x-1) > 1 做分类导论时增加换元u=(x+1)/(x-1) 12. 支持f(f(x))做还元的用法，令t=f(x) 13. 输入即可执行，不需要再点选择项 14. 提供已有等式/不等式的垂直列表显示 15. 点击彩色题目可看相关概念解释 16. 其它错误与bug: ipad 输入拦截，操作项与其解释不匹配，二次方程标准型判定不严格