Home
Class 12
MATHS
Let f(x)=1-x-x^3.Values of x not satisf...

Let `f(x)=1-x-x^3`.Values of x not satisfying the inequality, `1-f(x)-f^3(x)>f(1-5x)`

A

`(-2,0)`

B

`(2,oo)`

C

`(0,2)`

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
C

`f(x)=1-x-x^(3)`
`rArr" "f'(x)=-1-3x^(2)lt0` for all x
Now `1-f(x)-f^(3)(x)gtf(1-5x)`
`rArr" "f(f(x))gtf(1-5x)`
`rArr" "f(x)lt1-5x" (as f(x) is decreasing)"`
`rArr" "1-x-x^(3)lt1-5x`
`rArr" "x^(3)-4xgt0`
`rArr" "x(x-2)(x+2)gt0`
`rArr" "x in (-2,0)uu(2,oo)`
Promotional Banner

Topper's Solved these Questions

  • MONOTONOCITY AND NAXINA-MINIMA OF FUNCTIONS

    CENGAGE|Exercise Multiple Correct Answer Type|10 Videos
  • MONOTONOCITY AND NAXINA-MINIMA OF FUNCTIONS

    CENGAGE|Exercise Comprehension Type|6 Videos
  • MONOTONICITY AND MAXIMA MINIMA OF FUNCTIONS

    CENGAGE|Exercise JEE Advanced Previous Year|17 Videos
  • PAIR OF STRAIGHT LINES

    CENGAGE|Exercise Exercise (Numerical)|5 Videos

Similar Questions

Explore conceptually related problems

Let f(x)=1-x-x^(3) .Find all real values of x satisfying the inequality,1-f(x)-f^(3)(x)>f(1-5x)

Let f(x)=1-x-4x^(3),f:R rarr R then find the number of integrality satisfying the inequality 4f(x)^(3)+f(1-2x)+f(x)<1

If f(x)=2x+1 then the value of x satisfying the equation f(x)+f(f(x))+f(f(f(x)))+f(f(f(f(x)))=116 is equal to

Statement-1 : The function f defined as f(x) = a^(x) satisfies the inequality f(x_(1)) lt f(x_(2)) for x_(1) gt x_(2) when 0 lt a lt 1 . and Statement-2 : The function f defined as f(x) = a^(x) satisfies the inequality f(x_(1)) lt f(x_(2)) for x_(1) lt x_(2) when a gt 1 .

Let f(x)=x^(2)-3x+4, the value(s) of x which satisfies f(1)+f(x)=f(1)f(x) is

if F(x)=x^2-2x+3 then the set of values of x satisfying f(x-1)=f(x+1)

let f(x)=x^(2)-3x+4 the values of x which satisfies f(1)+f(x)=f(1)*f(x) is

Let f:R-{3}rarr R be a real valued function satisfying the functional equation 3f(x)+2f((3x+5)/(x-3))=4x+2 Then f(x) is given as