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Consider the function f(x) = x + ln(x) − x ln(x), where x lies in the interval (0, ∞). - Column 1 contains details about the zeros of f(x), f'(x), and f''(x). - Column 2 contains information about the behavior of f(x), f'(x), and f''(x) as x approaches infinity. - Column 3 contains details about the increasing or decreasing nature of f(x) and f'(x). Column 1: (I) f(x) = 0 for some x in (1, e²) (II) f'(x) = 0 for some x in (1, e) (III) f'(x) = 0 for some x in (0, 1) (IV) f''(x) = 0 for some x in (1, e) Column 2: (i) lim x→∞ f(x) = 0 (ii) lim x→∞ f(x) = −∞ (iii) lim x→∞ f'(x) = −∞ (iv) lim x→∞ f''(x) = 0 Column 3: (P) f is increasing on (0, 1) (Q) f is decreasing on (e, e²) (R) f' is increasing on (0, 1) (S) f' is decreasing on (e, e²) Which of the following options gives the correct combination?
- (I) (P)
- (III) (iii) (R)
- (IV) (iv) (S)
- (II) (ii) (Q)
Correct answer: (II) (ii) (Q)
Solution
The function f(x) and its derivatives provide insight into the behavior of the function, including its zeros, limits as x approaches infinity, and increasing or decreasing nature, which are crucial in determining the correct combination of characteristics.
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