Class 8 Maths – Chapter 14
Factorisation
STEP 2: Methods of Factorisation
Factorisation
STEP 2: Methods of Factorisation
🔹 Method 1: Factorisation by Taking Common Factor
If each term of an expression has a common factor, we take it out.
Example:
3x + 6 = 3(x + 2)
If each term of an expression has a common factor, we take it out.
Example:
3x + 6 = 3(x + 2)
🔹 Method 2: Factorisation by Grouping
This method is used when terms can be grouped in pairs having common factors.
Example:
ax + ay + bx + by
= a(x + y) + b(x + y)
= (a + b)(x + y)
This method is used when terms can be grouped in pairs having common factors.
Example:
ax + ay + bx + by
= a(x + y) + b(x + y)
= (a + b)(x + y)
🔹 Method 3: Factorisation Using Identities
Some algebraic identities help us to factorise expressions quickly.
Important identities:
(a + b)² = a² + 2ab + b²
(a − b)² = a² − 2ab + b²
a² − b² = (a − b)(a + b)
Some algebraic identities help us to factorise expressions quickly.
Important identities:
(a + b)² = a² + 2ab + b²
(a − b)² = a² − 2ab + b²
a² − b² = (a − b)(a + b)
🔹 Method 4: Factorisation of Simple Quadratic Expressions
First take common factors, then use identities if needed.
Example:
x² − 9 = (x − 3)(x + 3)
First take common factors, then use identities if needed.
Example:
x² − 9 = (x − 3)(x + 3)
🎯 Student Tip:
Always try common factor first → then grouping → then identities.
Always try common factor first → then grouping → then identities.
📘 Class 8 Mathematics – Complete Library
CBSE | NCERT | State Syllabus
Chapter 1: Rational Numbers
Chapter 2: Linear Equations in One Variable
Chapter 3: Understanding Quadrilaterals
Chapter 4: Practical Geometry
Chapter 5: Data Handling
Chapter 6: Squares and Square Roots
Chapter 7: Cubes and Cube Roots
- NCERT Notes
- MCQs
- Worksheet
- Worksheet Answers
- Mind Map & Easy Tricks
- Important Exam Questions
- Very Important Questions
No comments:
Post a Comment