# Function symbolicEqual Attempts to determine if two expressions are symbolically equal, i.e. one is the result of valid algebraic manipulations on the other. Currently, this simply checks if the difference of the two expressions simplifies down to 0. So there are two important caveats: 1. whether two expressions are symbolically equal depends on the manipulations allowed. Therefore, this function takes an optional third argument, which are the options that control the behavior as documented for the `simplify()` function. 2. it is in general intractable to find the minimal simplification of an arbitrarily complicated expression. So while a `true` value of `symbolicEqual` ensures that the two expressions can be manipulated to match each other, a `false` value does not absolutely rule this out. ## Syntax ```js symbolicEqual(expr1, expr2) symbolicEqual(expr1, expr2, options) ``` ### Parameters Parameter | Type | Description --------- | ---- | ----------- `expr1` | Node | string | The first expression to compare `expr2` | Node | string | The second expression to compare `options` | Object | Optional option object, passed to simplify ### Returns Type | Description ---- | ----------- boolean | Returns true if a valid manipulation making the expressions equal is found. ### Throws Type | Description ---- | ----------- ## Examples ```js symbolicEqual('x*y', 'y*x') // true symbolicEqual('x*y', 'y*x', {context: {multiply: {commutative: false}}}) //false symbolicEqual('x/y', '(y*x^(-1))^(-1)') // true symbolicEqual('abs(x)','x') // false symbolicEqual('abs(x)','x', simplify.positiveContext) // true ``` ## See also [simplify](simplify.md), [evaluate](evaluate.md)