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If Δ = bacaabcbacbc|0b-ac-aa-b0c-ba-cb-c0|, then show that ∆ is equal to zero. - Mathematics

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Question

If Δ = `|(0, "b" - "a", "c" - "a"),("a" - "b", 0, "c" - "b"),("a" - "c", "b" - "c", 0)|`, then show that ∆ is equal to zero.

Sum
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Solution

Interchanging rows and columns, we get

Δ = `|(0, "a" - "b", "a" - "c"),("b" - "a", 0, "b" - "c"),("c" - "a", "c" - "b", 0)|`

Taking ‘–1’ common from R1, R2 and R3, we get

Δ = `(-1)^3|(0, "b" - "a", "c" - "a"),("a" - "b", 0, "c" - "b"),("a" - "c", "b" - "c", 0)|`

= – Δ

⇒ 2Δ = 0 or Δ = 0

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Chapter 4: Determinants - Solved Examples [Page 71]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 4 Determinants
Solved Examples | Q 5 | Page 71

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