# Simplifying: simplify

### 5.12.14 Simplifying: simplify

The simplify command simplifies an expression. It behaves like normal for rational functions and algebraic extensions. For expressions containing transcendental functions, simplify tries first to rewrite them in terms of algebraically independent transcendental functions. For trigonometric expressions, this requires radian mode (check radian in the cas configuration, see Section 2.5.7, or input angle_radian:=1).

- simplify takes one argument:
  expr, an expression.
- simplify(expr) returns a simplified version of expr.

#### Examples.

- Input:
  simplify((x-1)*(x+1))
  Output:

  x2−1

- Input:
  simplify(3-54*sqrt(1/162))
  Output:

  −3

  √

  2

  +3

- Input:
  simplify((sin(3*x)+sin(7*x))/sin(5*x))
  Output:

  2 cos | ⎛ ⎝ | 2 x | ⎞ ⎠