Home
Class 12
MATHS
|log (e)|x|| =|k -1| -3 has four distict...

`|log _(e)|x|| =|k -1| -3` has four distict roots then k satisfies : (where `|x| lt d ^(2) , x ne 0)`

A

`(-4, -2)`

B

`(4,6)`

C

`(e ^(-1), e )`

D

`(d^(-2), e ^(-1))`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation \( | \log_e |x| | = |k - 1| - 3 \) and find the conditions on \( k \) such that the equation has four distinct roots, we can follow these steps: ### Step 1: Analyze the Equation The given equation is: \[ | \log_e |x| | = |k - 1| - 3 \] ### Step 2: Identify the Domain Since \( |x| < d^2 \) and \( x \neq 0 \), we know that \( |x| \) can take values in the interval \( (0, d^2) \). ### Step 3: Determine the Range of \( \log_e |x| \) For \( |x| \) in the interval \( (0, d^2) \): - As \( x \to 0 \), \( \log_e |x| \to -\infty \). - At \( |x| = d^2 \), \( \log_e |x| = \log_e (d^2) = 2 \log_e d \). Thus, the range of \( \log_e |x| \) is \( (-\infty, 2 \log_e d) \). ### Step 4: Analyze the Left Side of the Equation The left side \( | \log_e |x| | \) can take values: - From \( 0 \) to \( 2 \log_e d \) when \( \log_e |x| \) is positive. - From \( -\infty \) to \( 0 \) when \( \log_e |x| \) is negative. ### Step 5: Analyze the Right Side of the Equation The right side \( |k - 1| - 3 \) must be non-negative for the equation to have solutions: \[ |k - 1| - 3 \geq 0 \implies |k - 1| \geq 3 \] This gives us two cases: 1. \( k - 1 \geq 3 \implies k \geq 4 \) 2. \( k - 1 \leq -3 \implies k \leq -2 \) ### Step 6: Conditions for Four Distinct Roots For the equation to have four distinct roots, the value of \( |k - 1| - 3 \) must be such that it intersects the left side \( | \log_e |x| | \) at four points. Since \( | \log_e |x| | \) can take values from \( 0 \) to \( 2 \log_e d \), we require: \[ |k - 1| - 3 < 2 \log_e d \] This leads to: \[ |k - 1| < 2 \log_e d + 3 \] ### Step 7: Combine Conditions Combining the conditions from Steps 5 and 6, we have: 1. \( k \geq 4 \) or \( k \leq -2 \) 2. \( |k - 1| < 2 \log_e d + 3 \) ### Conclusion Thus, the values of \( k \) that satisfy the conditions for the equation to have four distinct roots are: - For \( k \geq 4 \): \( 4 \leq k < 2 \log_e d + 4 \) - For \( k \leq -2 \): \( -2 > k > 2 \log_e d - 2 \)
Promotional Banner

Topper's Solved these Questions

  • FUNCTION

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise COMPREHENSION TYPE PROBLEMS|13 Videos
  • FUNCTION

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise MATCHING TYPE PROBLEMS|6 Videos
  • FUNCTION

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise SUBJECTIVE TYPE PROBLEMS|33 Videos
  • ELLIPSE

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise Exercise-4 : Subjective Type Problems|2 Videos
  • HYPERBOLA

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise Exercise-4 : Subjective Type Problems|3 Videos

Similar Questions

Explore conceptually related problems

If the equation |x^2+b x+c|=k has four real roots, then a. b^2-4c > 0 and 0 0 and k > (4c-b^2)/4 d. none of these

If m and n are roots of the equation : (1)/(x)-(1)/(x-2)=3 , where x ne 0 and x ne 2 , find mxxn .

Find the value of k if x^3-3x+k=0 has three real distinct roots.

If f(x) = (x)/(1+(log x)(log x)....oo), AA x in [1, 3] is non-differentiable at x = k. Then, the value of [k^(2)] , is (where [*] denotes greatest integer function).

Let a, b be the roots of the equation x^(2) - 4 x +k_(1) = 0 and c , d the roots of the equation x^(2) - 36 x + k_(2) = 0 If a lt b lt c lt d and a, b,c,d are in G.P. then the product k_(1) k_(2) equals

Let I_(1) : (log_(x)2) (log_(2x)2) (log_(2)4x)gt1 I_(2) : x^((log_(10)x)^(2)-3(log_(10)x)+1) gt 1000 and solution of inequality I_(1) is ((1)/(a^(sqrt(a))),(1)/(b))cup(c, a^(sqrt(a))) and solution of inequality I_(2) is (d, oo) then answer the following Both root of equation dx^(2) - bx + k = 0, (k in R) are positive then k can not be

If k lt 0 , then the number of roots of the equation ke^(x)-x=0 , is

In the Delta ABCA gt B. If the measures of A and B satisfy the equation 3 sin x - 4 sin ^(3) x - k =0, 0 lt k lt 1. Then the measure of C is

Statement-1: There is a value of k for which the equation x^(3) - 3x + k = 0 has a root between 0 and 1. Statement-2: Between any two real roots of a polynomial there is a root of its derivation.

VIKAS GUPTA (BLACK BOOK) ENGLISH-FUNCTION -ONE OR MORE THAN ONE ANSWE IS/ARE CORRECT
  1. Let f (x) =||x^(2)-4x+3|-2|. Which of the following is/are correct ?

    Text Solution

    |

  2. Let f (x) =cos ^(-1) ((1-tan ^(2)(x//2))/(1+ tan ^(2) (x//2))) . Solv...

    Text Solution

    |

  3. |log (e)|x|| =|k -1| -3 has four distict roots then k satisfies : (whe...

    Text Solution

    |

  4. Which of the following functions are defined for all x in R? (Where [...

    Text Solution

    |

  5. Let f (x)= {{:(x ^(2),0lt x lt2),(2x-3, 2 le x lt3),(x+2, x ge3):} the...

    Text Solution

    |

  6. Let f:[-pi/3,(2pi)/3] rarr [0,4] be a function defined as f(x)=sqrt(3)...

    Text Solution

    |

  7. Let f (x) be invertible function and let f ^(-1) (x) be is inverse. Le...

    Text Solution

    |

  8. In function f(x)=cos^(-1)x+cos^(-1)(x/2+(sqrt(3-3x^2))/2) , then Range...

    Text Solution

    |

  9. Which option (s) is/are ture ?

    Text Solution

    |

  10. If f (x) =[ln (x)/(e)] +[ln (e)/(x)], where [.] denotes greatest inter...

    Text Solution

    |

  11. If f (x)= {{:(x ^(3), , x =Q),(-x ^(3),,x ne Q):}, then :

    Text Solution

    |

  12. Let f(x) be a real valued function such that f(0)=1/2 and f(x+y)=f(x)f...

    Text Solution

    |

  13. f(x) is an even periodic function with period 10. In [0,5] f (x)= {{:(...

    Text Solution

    |

  14. For the equation (e^-x)/(x+1) which of the following statement(s) is/a...

    Text Solution

    |

  15. . For x in R^+, if x, [x], {x} are in harmonic progression then the va...

    Text Solution

    |

  16. The equation ∣∣x−1∣+a∣=4 can have real solutions for x if a belongs to...

    Text Solution

    |

  17. If the domain of f (x) =1/picos ^(-1)[log (3) ((x^(2))/(3))] where, x ...

    Text Solution

    |

  18. The number of real values of x satisfying the equation;[(2x+1)/3]+[(4x...

    Text Solution

    |

  19. Let f (x= sin ^(6) ((x )/(4)) + cos ^(6) ((x)/(4)). If f ^(n) (x) deno...

    Text Solution

    |

  20. Which of the following is (are) incorrect ?

    Text Solution

    |