Check sibling questions

Ex 4.1, 3 - Show that |2A| = 4|A|, if A = [1 2 4 2] - Ex 4.1

Ex 4.1, 3 - Chapter 4 Class 12 Determinants - Part 2

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Transcript

Ex 4.1, 3 If A = [■8(1&[email protected]&2)] , then show that |2A| = 4|A| We need to prove |2A| = 4|A| Taking L.H.S |2A| First calculating 2 A 2A = 2 [■8(1&[email protected]&2)] = [■8( 2 × 1&2 × 2@ 2 × 4&2 × 2)] = [■8(2&[email protected]&4)] So, |2A| = |■8(2&[email protected]&4)| = 2(4) – 8 (4) = 8 – 32 = –24 Taking R.H.S 4|A| As A = [■8(1&[email protected]&2)] So |A| = |■8(1&[email protected]&2)| = 1 (2) – 4 (2) = 2 – 8 = –6 Hence, 4|A| = 4 (−6) = −24 = L.H.S ∴ L.H.S = R.H.S Hence proved

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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 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.