𝑥 代数计算器Algebra Calculator
代数式化简、展开、因式分解，解方程（一元多项式方程，含复数根），以及代入数值求值，结果给出精确形式和 LaTeX。Simplify, expand and factor algebraic expressions, solve equations (single-variable polynomial equations, complex roots included) and evaluate with a value substituted — exact results with LaTeX.
使用说明与常见问题How-to & FAQ
「代数计算器」是什么？What is the Algebra Calculator tool?
代数式化简、展开、因式分解，解方程（一元多项式方程，含复数根），以及代入数值求值，结果给出精确形式和 LaTeX。Simplify, expand and factor algebraic expressions, solve equations (single-variable polynomial equations, complex roots included) and evaluate with a value substituted — exact results with LaTeX.
如何使用「代数计算器」？How do I use the Algebra Calculator tool?
在「代数计算器」中，按需设置「操作」、「表达式 / 方程」、「变量」、「变量的值」等选项，然后点击「计算」按钮即可。In the Algebra Calculator: Set "Operation", "Expression / equation", "Variable", "Value", then click "Calculate".
能解哪些方程？Which equations can it solve?
一元方程，尤其是多项式方程：一次、二次给出精确根（如 √2），高次方程能分解时给出精确根，否则给出数值近似根（含复数根）。暂不支持方程组和不等式。Single-variable equations, especially polynomials: linear and quadratic give exact roots (like √2); higher degrees give exact roots when they factor, otherwise numeric approximations (including complex roots). Systems of equations and inequalities are not supported yet.
三角方程能解吗？Can it solve trig equations?
只能给出一个主值解（如 sin(x) = 0.5 给出 π/6），不会列出全部解或通解；需要全部解时请自行加上周期并检查同一周期内的其他解。Only one principal solution is returned (sin(x) = 0.5 gives π/6); it does not list every solution or the general solution — add the period yourself and check for other solutions within one period.
支持哪些写法？What syntax is supported?
四则运算 + - * /、乘方 ^、括号，函数 sin cos tan asin acos atan sinh cosh tanh sqrt abs exp log（自然对数，ln 也可以）等，常数 pi 和 e。乘号可以省略（2x、3sin(x)），也可以用 ×、÷、π、√。+ - * /, powers with ^, parentheses, functions such as sin cos tan asin acos atan sinh cosh tanh sqrt abs exp log (natural log; ln also works), and the constants pi and e. Multiplication can be implicit (2x, 3sin(x)); ×, ÷, π and √ are accepted too.
用的是什么计算引擎？What engine does it use?
开源符号计算库 nerdamer（Apache-2.0 许可），在独立的后台线程（Web Worker）中运行，超过 10 秒会自动停止，不会卡住页面；所有计算都在本地完成。The open-source symbolic library nerdamer (Apache-2.0), running in a background Web Worker that stops after 10 seconds so the page never freezes; everything is computed locally.
计算精度如何？How precise are the results?
「代数计算器」使用 JavaScript 双精度浮点数（约 15–16 位有效数字）；极大或极小的数值可能存在精度误差。The Algebra Calculator uses double-precision floating point (about 15–16 significant digits); very large or very small values may lose precision.
「代数计算器」免费吗？需要注册吗？Is the Algebra Calculator free? Do I need an account?
「代数计算器」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Algebra Calculator is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.