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Question
Evaluate `int 1/(x log x) "d"x`
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Solution
Let I = `int 1/(x log x) "d"x`
Put log x = t
∴ `1/x "d"x` = dt
∴ I = `int1/"t" "dt"` = log|t| + c
∴ I = log |log x| + c
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