JEE Advanced2008MathematicsApplication of DerivativesActual
The total number of local maxima and local minima of the function f(x)= array lc (2+x)^3 ; & -3 < x -1 x^ 2 3 ; & -1 < x < 2 array . is
Options
- A0
- B1
- C2
- D3
Correct answer
C. 2
Step-by-step solution
Given that, f(x)= array l (2+x)^3 ;-3 Clearly, f^ (x) changes its sign at x=-1 from + ve to -ve and so f(x) has local maxima at x=-1 . Also, f^ (0) does not exist but f^ (0⁻ ) < 0 and f^ (0⁺ ) < 0 . It can only be inferred that f(x) has a possibility of a minima at x=0 . Hence, the given function has one local maxima at x=-1 and one local minima at x=0 .