Which algebraic identity is used to factorise the difference of two cubes, \(a^3-b^3\)?
Answer and explanation
Correct answer: \(a^3-b^3=(a-b)(a^2+ab+b^2)\)
Option A is correct because expanding \((a-b)(a^2+ab+b^2)\) cancels the middle terms and gives \(a^3-b^3\). Option B is for a sum of cubes. Exam tip: when powers are 3, check cube identities first.
Frequently asked questions
What is the correct answer to this question?
\(a^3-b^3=(a-b)(a^2+ab+b^2)\)
Why is this the correct answer?
Option A is correct because expanding \((a-b)(a^2+ab+b^2)\) cancels the middle terms and gives \(a^3-b^3\). Option B is for a sum of cubes. Exam tip: when powers are 3, check cube identities first.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Exploring Algebraic Identities. Topic: Algebraic identities.
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