COMEDK2024MathematicsApplication of DerivativesActual
The function y= x-x is
Options
- Adecreasing in (0, 4 ) and increasing in ( 4 , 2 )
- Ba decreasing function in (0, 2 )
- Can increasing function in (0, 2 )
- Dincreasing in (0, 4 ) and decreasing in ( 4 , 2 )
Correct answer
C. an increasing function in (0, 2 )
Step-by-step solution
Let f(x) = x - x . To determine the intervals of increase or decrease, find the first derivative of f(x) with respect to x . f'(x) = d dx ( x - x) = ^2 x - 1 . Using the trigonometric identity ^2 x - 1 = ^2 x , we have f'(x) = ^2 x . For x (0, 2 ) , x > 0 , which implies ^2 x > 0 . Since f'(x) > 0 for all x (0, 2 ) , the function f(x) = x - x is strictly increasing in the interval (0, 2 ) . Answer: an increasing function in (0, 2 )