If A = [8(0 2 3 -4)] and kA = [8(0 3a 2b 24)], then the values of 𝑘,𝑎 and 𝑏 respectively are:

(a) −6, −12, −18          (b) −6, −4, −9

(c) −6, 4, 9                   (d) −6, 12, 18

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Question 32 If A = [■8(0&2@3&−4)] and kA = [■8(0&3𝑎@2𝑏&24)], then the values of 𝑘,𝑎 and 𝑏 respectively are: (a) −6, −12, −18 (b) −6, −4, −9 (c) −6, 4, 9 (d) −6, 12, 18 Now, A = [■8(0&2@3&−4)] kA = k [■8(0&2@3&−4)] kA = [■8(0 × 𝑘&2 × 𝑘@3 × 𝑘&−4 × 𝑘)] kA = [■8(0&2𝑘@3𝑘&−4𝑘)] Putting value of kA [■8(0&3𝑎@2𝑏&24)] = [■8(0&2𝑘@3𝑘&−4𝑘)] Thus, 24 = −4k −4k = 24 k = 24/(−4) k = −6 Also, 3a = 2k 3a = 2(−6) 3a = −12 a = (−12)/3 a = −4 So, the correct answer is (B) [■8(0&3𝑎@2𝑏&24)] = [■8(0&2𝑘@3𝑘&−4𝑘)] Thus, 24 = −4k −4k = 24 k = 24/(−4) k = −6 Also, 3a = 2k 3a = 2(−6) 3a = −12 a = (−12)/3 a = −4 2b = 3k 2b = 3(−6) 2b = −18 b = (−18)/2 b = −9 Thus, k = −6, a = −4, b = −9 So, the correct answer is (B)

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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.