If p > q >1 and 0 < a < 1 then which of the following is correct option?
If p > q >1 and 0 < a < 1 then which of the following is correct option? Correct Answer log<sub>a</sub>(p – a) < log<sub>a</sub>(q – a)
Explanation:
For a log function with base a as 0 < a < 1, the graph of the function can be drawn as bellow
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The above graph is valid for,
x > 0 and 0 < a < 1
Since the function y = logax is a decreasing function for base a ∈ (0, 1). So, while operating loga on a given inequality, the sign of the inequality will change.
Calculation:
Given:
p > q > 1
⇒ (p – 1) > (q – 1) > 0
Operating log function on both sides,
⇒ loga(p -1) < loga(q - 1)
⇒ Option 3 is correct.