Which of the following identities correctly represents the square expansion of \,\((a+b+c)^2\)?
Answer and explanation
Correct answer: \((a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ca\)
Squaring a sum of three terms gives the square of each term and twice every pairwise product. Hence \(2ab\), \(2bc\), and \(2ca\) must all appear. Exam tip: check that no cross-product is missing its factor of 2.
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What is the correct answer to this question?
\((a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ca\)
Why is this the correct answer?
Squaring a sum of three terms gives the square of each term and twice every pairwise product. Hence \(2ab\), \(2bc\), and \(2ca\) must all appear. Exam tip: check that no cross-product is missing its factor of 2.
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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