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Question
If 2 log x + 1 = log 360, find: log(2 x -2)
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Solution
log(2 x -2)
2logx + 1 = log360
⇒ logx2 + log10 = log360
⇒ log(10x2) = log360
⇒ 10x2 = 360
⇒ x2 = `(360)/(10)` = 36
⇒ x = `sqrt(36)` = ±6
As negative value is rejected,
∴ x = 6
∴ log (2x - 2)
= log(2.6 - 2)
= log 10
= 1.
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