MHT CET202415 May 2024Morning ShiftMathematicsApplication of DerivativesActual
If f (x)=x^3-10 x^2+200 x-10 , then
Options
- Af (x) is decreasing in (- , 10] and increasing in [10, )
- Bf (x) is increasing in (- , 10] and decreasing in [10, )
- Cf (x) is increasing throughout real line
- Df (x) is decreasing throughout real line
Correct answer
C. f (x) is increasing throughout real line
Step-by-step solution
aligned & f (x)=x^3-10 x^2+200 x-10 & f ^ (x)=3 x^2-20 x+200 aligned For f (x) to be increasing f ^ (x) 0 aligned & 3 x^2-20 x+200 0 & 3 (x^2- 20 3 x+ 200 3 + 100 9 - 100 9 ) 0 & 3 [ (x- 10 3 )^2+ 500 9 ] 0 & 3 (x- 10 3 )^2+ 500 3 0 aligned Always increasing throughout real line.