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Answer the following: If log(a+b2)=12(loga+logb), then show that a = b - Mathematics and Statistics

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Question

Answer the following:

If `log (("a" + "b")/2) = 1/2(log"a" + log"b")`, then show that a = b

Sum

Solution

`log (("a" + "b")/2) = 1/2(log"a" + log"b")`

∴ `2 log (("a" + "b")/2)` = log a + log b

∴ `log (("a" + "b")/2)^2` = log ab

∴ `("a" + "b")^2/4` = ab

∴ a2 + 2ab + b2 = 4ab

∴ a2 + 2ab – 4ab + b2 = 0

∴ a2 – 2ab + b2 = 0

∴ (a – b)2 = 0

∴ a – b = 0

∴ a = b

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

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