BITSAT2023MathematicsApplication of DerivativesActual
The function f(x)= ⁻¹( x+ x) is an increasing function in
Options
- A( 4 , 2 )
- B(- 2 , 4 )
- C(0, 2 )
- D(- 2 , 2 )
Correct answer
B. (- 2 , 4 )
Step-by-step solution
Since, f(x)= ⁻¹( x+ x) f ^ ( x )= 1 1+( x + x )^2 ( x - x ) = 2 (x+ 4 ) 1+( x+ x)^2 f(x) is increasing if f^ (x)>0 (x+ 4 )>0 - 2 < x+ 4 < 2 - 3 2 < x+ 4