Quick start
- Type the expression, for example (x + 2)^2 - (x - 1)(x + 3).
- Leave the second box empty to only simplify, or enter a value such as 4 to evaluate.
- Read the expanded form and the simplified result.
Example
(x + 2)² expands to x² + 4x + 4, and (x − 1)(x + 3) expands to x² + 2x − 3. Subtracting gives x² + 4x + 4 − x² − 2x + 3 = 2x + 7. At x = 4 the value is 15.
Rules worth knowing
- Like terms share the same variable and power: 3x² and −x² combine to 2x², but 3x² and 3x do not.
- (a + b)² = a² + 2ab + b², not a² + b². The middle term is easy to forget.
- A minus sign in front of brackets changes the sign of every term inside.
Typing tips
Use ^ for powers and * or brackets for multiplication. 3x, 3*x and 3(x) are all read the same. Fractions work too, such as (x^2 - 1)/(x - 1).
Common questions
Can it simplify fractions with x in them?
It can tidy many of them, such as (x² − 1)/(x − 1), which reduces to x + 1 for x ≠ 1.
Can I use other letters?
Simplifying works best with x. Evaluating needs x as the variable.
Why is my answer in a different order than my textbook?
Terms can be written in any order. 7 + 2x and 2x + 7 are the same expression.