Check sibling questions

Example 27 - Solve system of equations 2x + 5y = 1 3x+2y=7 - Examples

Example 27 - Chapter 4 Class 12 Determinants - Part 2
Example 27 - Chapter 4 Class 12 Determinants - Part 3
Example 27 - Chapter 4 Class 12 Determinants - Part 4

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Transcript

A﷯ = 2﷮5﷮3﷮2﷯﷯ = 2 × 2 – 5 × 3 = 4 – 15 = – 11 Since 𝑨﷯ ≠ 0, System is consistent and the system of equations has a unique solution AX = B X = A-1 B Step 3 Calculating X = A-1 B Here, A-1 = 1﷮|A|﷯ adj (A) adj A = 2﷮5﷮3﷮2﷯﷯ = 2﷮−5﷮−3﷮2﷯﷯ Now, A-1 = 1﷮|A|﷯ adj A Putting values = 1﷮−11﷯ 2﷮−5﷮−3﷮2﷯﷯ & B = 1﷮7﷯﷯ Now X = A-1 B 𝑥﷮𝑦﷯﷯ = −1﷮11﷯ 2﷮−5﷮−3﷮2﷯﷯ 1﷮7﷯﷯ = −1﷮11﷯ 2 1﷯+ −5﷯7﷮−3 1﷯+2(7)﷯﷯ = −1﷮11﷯ 2−35﷮−3+14﷯﷯ 𝑥﷮𝑦﷯﷯ = −1﷮11﷯ −33﷮11﷯﷯ = −33 × −1﷮11﷯﷮11 × −1﷮11﷯﷯﷯ 𝑥﷮𝑦﷯﷯ = 3﷮−1﷯﷯ Hence x = 3 & y = – 1

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.