整个系统具有的功能：响应各个数字键，实现加、减、乘、除、x^y、lnx、x!、sinx、cosx、tanx、清空、求倒数等基本功能；-The whole system has a function: response of each number key, add, subtract, multiply, divide, x ^ y, lnx, x, sinx, cosx, tanx, empty, seeking reciprocal basic functions !