Question
Mathematics Question on Functions
Match List-I with List-II.
\begin{array}{|c|c|} \hline \textbf{List-I (Function)} & \textbf{List-II (Interval in which function is increasing)} \\\ \hline \frac{x}{\log_e x} & (-\infty, -2) \cup (2, \infty) \\\ \hline \frac{x}{2} + \frac{2}{x}, x \neq 0 & \left(-\frac{\pi}{4}, \frac{\pi}{4}\right) \\\ \hline x^x, x > 0 & \left(\frac{1}{e}, \infty\right) \\\ \hline \sin x - \cos x & (e, \infty) \\\ \hline \end{array}
Choose the correct answer from the options given below:
(A-II), (B-I), (C-III), (D-IV)
(A-I), (B-III), (C-IV), (D-II)
(A-IV), (B-I), (C-III), (D-II)
(A-III), (B-IV), (C-I), (D-II)
(A-IV), (B-I), (C-III), (D-II)
Solution
(A) The function logexx is increasing for x>e (interval (IV)).
(B) The function x−2x2+1 is increasing in the intervals (−∞,−2)∪(2,∞) (interval (I)).
(C) The exponential function ex is increasing for x>0, and the interval where the function is increasing for ex is (e1,∞) (interval (III)).
(D) The function sinx−cosx is increasing in the interval (−4π,4π) (interval (II)).