Let
Then the set of all values of , for which has maximum value at , is :
Then the set of all values of , for which has maximum value at , is :
- (A)
- (B)
- (C)✓ Correct
- (D)
Answer: (C)
Solution
At : .
For : (discriminant negative), so is increasing.
For : , so is decreasing.
For maximum at , we need :
Also (for the logarithm), so .
Thus , giving .
For : (discriminant negative), so is increasing.
For : , so is decreasing.
For maximum at , we need :
Also (for the logarithm), so .
Thus , giving .
JEE Main · 2022 · 26 Jul 2022 · Shift 1 · Single correct option