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Answer the following: Solve for x, logx (8x – 3) – logx 4 = 2 - Mathematics and Statistics

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Question

Answer the following:

Solve for x, logx (8x – 3) – logx 4 = 2

Sum

Solution

logx (8x – 3) – logx 4 = 2

∴ `log_x ((8x - 3)/4)` = 2

∴ x2 = `(8x - 3)/4`

∴ 4x2 = 8x – 3

∴ 4x2 – 8x + 3 = 0

∴ 4x2 – 2x – 6x + 3 = 0

∴ 2x(2x – 1) – 3 (2x – 1) = 0

∴ (2x – 1) (2x – 3) = 0

∴ 2x – 1 = 0 or 2x – 3 = 0

∴ x = `1/2` or x = `3/2`

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

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