# Summary

1. A combination of constants & variables connected by +, -, Ã— and Â¸ is known as algebraic expression.

2. A symbol having a fixed numerical value is called a constant. A symbol which takes on various numerical values in known as variable.

3. Terms are added to form expressions.

4. Expression contain exactly one, two and three terms are called monomial, binomial and trinomial respectively.

5. An algebraic expression in which the variables involved have only non-negative integral powers is called a polynomial.

6. Like terms one formed from the same variables and the powers of these variables are the same. Coefficients of like terms need not be the same.

7. While adding polynomial, arrange the like terms, unlike terms separately and add the like terms only. The same rule is followed for subtraction also.

8. For multiplication each term of one polynomial is multiplied by each term of the other polynomial.

9. An identity is an equality, which is true for all values of the variables in the equality.

10. The standard identities are

11. Another identity