Question
Question: If log<sub>0.3</sub> (x – 1) \< log<sub>0.09</sub> (x – 1), then x lies in the interval -...
If log0.3 (x – 1) < log0.09 (x – 1), then x lies in the interval -
A
(2, ¥)
B
(1, 2)
C
(–2, –1)
D
None of these
Answer
(2, ¥)
Explanation
Solution
log0.3 (x – 1) < log(0.3)2 (x – 1)
̃ log0.3 (x – 1) < 21 log0.3 (x – 1)
̃ log0.3 (x – 1)2 < log0.3 (x – 1)
(x – 1)2 > (x – 1)
(x – 1) (x – 2) > 0 ̃ x < 1 or x > 2
But log (x – 1) is defined if x – 1 > 0 ̃ x > 1
Common value is x > 2 ̃ (2, ¥)