📘 Class 8 Maths – Chapter 14: Factorisation
STEP 10: Important Exam Questions (VSA / SA / LA)
✍️ Very Short Answer (VSA)
Q1. What is factorisation?
Answer: Factorisation is the process of writing an algebraic expression as a product of its factors.
Q2. Write the identity for a² − b².
Answer: a² − b² = (a − b)(a + b)
✍️ Short Answer (SA)
Q3. Factorise: 8x + 16
Step 1: Take common factor 8
= 8(x + 2)
Answer: 8(x + 2)
Q4. Factorise: x² − 49
This is of the form a² − b²
= (x − 7)(x + 7)
Answer: (x − 7)(x + 7)
✍️ Long Answer (LA)
Q5. Factorise: x² + 11x + 30
Step 1: Find two numbers whose product is 30 and sum is 11
→ 5 and 6
Step 2: Split the middle term
= x² + 5x + 6x + 30
Step 3: Group terms
= x(x + 5) + 6(x + 5)
Step 4: Take common factor (x + 5)
= (x + 5)(x + 6)
Answer: (x + 5)(x + 6)
🎯 Examiner’s Tips
- Write identities clearly
- Do not skip steps in factorisation
- Final answer must be in brackets
- Neat presentation = more confidence to examiner
📌 Remember
✔ Common factor first
✔ Then identities
✔ Then grouping method
📘 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
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