What is Factorisation –

When an expression is the product of two or more expressions, then each of the expressions is called a factor of the given expression.

The process of writing a given expression as the product of two or more factors is called factorisation.

Prime Factor Form-If we write the factors of a number in such a way that all the factors are prime numbers then it is said to be a prime factor form.

Factors of Algebraic Expressions-Like any natural number, an algebraic expression is also the product of its factors. In the case of algebraic expression, it is said to be an irreducible form instead of prime factor form.

Factorisation of a given Algebraic Expression-

• Type I- To factorise a polynomial whose term have a common monomial fcator
• Type-II -When the given algebraic expression contains common binomial factors.
• Type-III-By grouping suitable terms( By re grouping)

Examples of TYPE-I

(a) 14x-14y = 14(x-y)

(b) ab+bc+be= b(a+c+e)

Examples of TYPE-II

(a) 4z(2x+3y)- 3z(2x+3y) = (2x+3y)(4z+3z)

(b)

Factorising Perfect Trinomial Squares

Method-

1.determine whether the trinomial is a perfect square trinomial by the following rule

• Two terms must be perfect squares and must be preceded by plus signs.
• the remaining term must be twice of the square roots of th eperfect square terms.

2.if the trinomial is a perfect trinomial square,fctorise asfollows:

• find the square roots of the two perfect square terms
• connect them with the signof the remaining term
• indicate that the binomial is to be used twice as a factor.

Factorising Difference of Two Squares.

Method-

• find th square roots of the two square terms.
• write the sumof the two square roots asone of th efactors
• write the difference of the two square roots as the other factor.

Factorisation_Class08_Video Solution

Worksheet in pdf format

Factorisation_Class08_ NCERT Book Link

https://ncert.nic.in/textbook.php

Factorisation_Class08_ FAQ

Q1. Can we use middle term splitting for factorisation .

Ans- yes offcourse

Q2. Is regrouping useful in this topic

Ans- We can get some factorising by using re-grouping only, therefor it is useful.