MHT CET202314 May 2023Morning ShiftMathematicsApplication of DerivativesActual
The maximum value of the function f(x)=3 x^3-18 x^2+27 x-40 on the set S = x R / x^2+30 11 x is
Options
- A122
- B-122
- C-222
- D222
Correct answer
A. 122
Step-by-step solution
aligned S & = x R / x^2+30 11 x & = x R / x^2-11 x+30 0 & = x R /(x-5)(x-6) 0 & = x R / x [5,6] f (x) & =3 x^3-18 x^2+27 x-40 f ^ (x) & =9 x^2-36 x+27 & =9(x-1)(x-3)>0 x [5,6] aligned f (x) is increasing in [5,6] . aligned Maximum value & = f (6) & =3(6)^3-18(6)^2+27(6)-40 & =122 aligned