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Answer the following: If log2a4=log2b6=log2c3k and a3b2c = 1 find the value of k - Mathematics and Statistics

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Question

Answer the following:

If `log_2"a"/4 = log_2"b"/6 = log_2"c"/(3"k")` and a3b2c = 1 find the value of k

Sum

Solution

Let `log_2"a"/4 = log_2"b"/6 = log_2"c"/(3"k")` = R

∴ log2 a = 4R, log2 b = 6R, log2 c = 3kR

Now, a3b2c = 1

∴ log2 (a3b2c) = log2 1

∴ log2 a3 + log2 b2 + log2 c = 0

∴ 3 log2 a + 2 log2 b + log2 c = 0

∴ 3(4R) + 2(6R) +3kR = 0

∴ 12R + 12R + 3kR = 0

∴ 24R + 3kR = 0

∴ 3kR = – 24R

∴ k = – 8

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Chapter 6: Functions - Miscellaneous Exercise 6.2 [Page 131]

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