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Ex 4.2
Ex 4.2, 2 Important
Ex 4.2, 3 You are here
Ex 4.2, 4
Ex 4.2, 5 Important
Ex 4.2, 6 Important
Ex 4.2, 7 Important
Ex 4.2, 8 (i) Important
Ex 4.2, 8 (ii)
Ex 4.2, 9 Important
Ex 4.2, 10 (i)
Ex 4.2, 10 (ii) Important
Ex 4.2, 11 (i)
Ex 4.2, 11 (ii) Important
Ex 4.2, 12 Important
Ex 4.2, 13 Important
Ex 4.2, 14 Important
Ex 4.2, 15 (MCQ) Important
Ex 4.2, 16 (MCQ)
Last updated at Jan. 22, 2020 by Teachoo
Ex 4.2, 3 Using the property of determinants and without expanding, prove that: |■8(2&7&65@3&8&75@5&9&86)| = 0 |■8(2&7&65@3&8&75@5&9&86)| Applying C3 → C3 − C1 = |■8(2&7&𝟔𝟓−𝟐@3&8&𝟕𝟓−𝟑@5&9&𝟖𝟔−𝟓)| = |■8(2&7&63@3&8&72@5&9&81)| Rough 65 – 2 = 63, 63/7 = 9 75 – 3 = 72, 72/8 = 9 86 – 5 = 81, 81/9 = 9 = |■8(2&7&𝟗 × 7@3&8&𝟗 ×8@5&9&𝟗 × 9)| Taking out 9 common from C3 = 9 |■8(2&𝟕&𝟕@3&𝟖&𝟖@5&𝟗&𝟗)| Here, C2 and C3 are identical = 9 × 0 = 0 Thus, |■8(2&7&65@3&8&75@5&9&86)| = 0 Hence proved Using Property: If any two row or column are identical, then value of determinant is zero