"计算器" "." "deg" "rad" "清除" "del" "欧拉数" "圆周率" "小数点" "左括号" "右括号" "余弦" "自然对数" "对数" "正弦" "正切" "反余弦" "反正弦" "反正切" "10 的次方" "指数函数" "平方" "加" "除" "阶乘" "乘" "百分比符号" "幂数" "平方根" "减" "角度模式" "弧度模式" "切换成角度" "切换成弧度" "等于" "清除" "删除" "显示反函数" "隐藏反函数" "不是数字" "表达式错误" "已中止" "无限值？" "不能除以 0" "文本已复制" "计算已取消" "已超时。可能是无限值或未定义的值。" "延长超时时间" "关闭" "（精确）" "（最后一位数字 ±1）" "在结果中显示前导数" "以分数形式显示结果" "开放源代码许可"