# Documentation

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# Formula Manipulation and Simplification

Simplify or modify expressions, substitute parts of expressions

Transform your expression into the particular form you require (expanded, factored, or expressed in particular terms) by choosing the appropriate function. See Choose Function to Rearrange Expression. If you just need a simpler expression, use `simplify`. You also can substitute for any part of an expression with another value by using `subs`.

## Functions

 `simplify` Algebraic simplification `simplifyFraction` Symbolic simplification of fractions `subexpr` Rewrite symbolic expression in terms of common subexpressions `pretty` Prettyprint symbolic expressions

#### Polynomials & Fractions

 `coeffs` Coefficients of polynomial `expand` Symbolic expansion of polynomials and elementary functions `horner` Horner nested polynomial representation `numden` Extract numerator and denominator `partfrac` Partial fraction decomposition

#### Rewriting & Decomposition

 `children` Subexpressions or terms of symbolic expression `collect` Collect coefficients `combine` Combine terms of identical algebraic structure `compose` Functional composition `divisors` Divisors of integer or expression `factor` Factorization `isolate` Isolate variable or expression in equation `lhs` Left side (LHS) of equation `rewrite` Rewrite expression in terms of another function `rhs` Right side (RHS) of equation

#### Display

 `pretty` Prettyprint symbolic expressions
 `subexpr` Rewrite symbolic expression in terms of common subexpressions `subs` Symbolic substitution

## Topics

Choose Function to Rearrange Expression

Several functions are available to manipulate expressions. Understand which function to use.

Simplify Symbolic Expressions

Simplifying symbolic expressions, including assumptions and additional options.

Substitute Variables in Symbolic Expressions

Substitute variables with other variables, numbers, vectors, or matrices.

Evaluate Symbolic Expressions Using subs

Evaluate expressions and functions after their variables are assigned values.

Abbreviate Common Terms in Long Expressions

Simplify the display of long expressions by abbreviating common terms.