Home
Class 12
MATHS
Let f(x) = |x -1| + |x-2| + |x-3| , matc...

Let `f(x) = |x -1| + |x-2| + |x-3|` , match the column I for the value of k column II.
`{:("Column - I" , " Column -II"),("(A) f(x) = k has no solution " ,"(p) 1 " ),("(B) f(x)=k has only one solution" , "(q) 2"),(" (C) f(x) = k has two solution of same sign " , "(r) 4"),("(D) f(x)= k has two solution of opposite sign" , "(s) 5"),(,"(t) 8"):}`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the function \( f(x) = |x - 1| + |x - 2| + |x - 3| \) and determine how many solutions the equation \( f(x) = k \) has for various values of \( k \). ### Step-by-Step Solution: 1. **Identify the critical points**: The critical points of the function occur where the absolute values change, which are at \( x = 1, 2, 3 \). These points will help us divide the number line into intervals. 2. **Analyze the intervals**: The intervals created by these points are: - \( (-\infty, 1) \) - \( [1, 2) \) - \( [2, 3) \) - \( [3, \infty) \) 3. **Determine the function behavior in each interval**: - For \( x < 1 \): \[ f(x) = -(x - 1) - (x - 2) - (x - 3) = -3x + 6 \] - For \( 1 \leq x < 2 \): \[ f(x) = (x - 1) - (x - 2) - (x - 3) = -x + 4 \] - For \( 2 \leq x < 3 \): \[ f(x) = (x - 1) + (x - 2) - (x - 3) = x + 2 \] - For \( x \geq 3 \): \[ f(x) = (x - 1) + (x - 2) + (x - 3) = 3x - 6 \] 4. **Evaluate the function at critical points**: - \( f(1) = |1 - 1| + |1 - 2| + |1 - 3| = 0 + 1 + 2 = 3 \) - \( f(2) = |2 - 1| + |2 - 2| + |2 - 3| = 1 + 0 + 1 = 2 \) - \( f(3) = |3 - 1| + |3 - 2| + |3 - 3| = 2 + 1 + 0 = 3 \) 5. **Determine the minimum value of \( f(x) \)**: - The minimum value occurs at \( x = 2 \), where \( f(2) = 2 \). 6. **Determine the behavior of \( f(x) \)**: - As \( x \) approaches \( -\infty \), \( f(x) \) approaches \( +\infty \). - As \( x \) approaches \( +\infty \), \( f(x) \) also approaches \( +\infty \). - The function is symmetric around \( x = 2 \). 7. **Match the values of \( k \) with the number of solutions**: - \( k < 2 \): \( f(x) = k \) has no solution (A matches with p). - \( k = 2 \): \( f(x) = k \) has only one solution (B matches with q). - \( 2 < k < 3 \): \( f(x) = k \) has two solutions of the same sign (C matches with r). - \( k = 3 \): \( f(x) = k \) has two solutions of opposite sign (D matches with s). - \( k > 3 \): \( f(x) = k \) has two solutions of opposite sign (D matches with t). ### Final Matching: - (A) \( f(x) = k \) has no solution → (p) 1 - (B) \( f(x) = k \) has only one solution → (q) 2 - (C) \( f(x) = k \) has two solutions of the same sign → (r) 4 - (D) \( f(x) = k \) has two solutions of opposite sign → (s) 5 - \( k = 8 \) → (t) 8
Promotional Banner

Topper's Solved these Questions

  • COMPLEX NUMBERS AND QUADRATIC EQUATIONS

    AAKASH INSTITUTE ENGLISH|Exercise section-G( Integer Answer type Questions)|8 Videos
  • COMPLEX NUMBERS AND QUADRATIC EQUATIONS

    AAKASH INSTITUTE ENGLISH|Exercise section-H ( Multiple True-False Type Questions|5 Videos
  • COMPLEX NUMBERS AND QUADRATIC EQUATIONS

    AAKASH INSTITUTE ENGLISH|Exercise Assertion -Reason Type Questions|19 Videos
  • BINOMIAL THEOREM

    AAKASH INSTITUTE ENGLISH|Exercise Assignment (section-J) Objective type question (Aakash Challengers Questions)|4 Videos
  • CONIC SECTIONS

    AAKASH INSTITUTE ENGLISH|Exercise SECTION - J ( Aakash Challengers Questions )|16 Videos

Similar Questions

Explore conceptually related problems

For f to be continuous at x = f(0) is given by {:("Column- I " , " Column - II"),("(A)" f(x) = (ln(1 +4x))/x, "(p)" 1/4),("(B)" f(x)=(ln(4+x)-ln4)/x , "(q) 0"),("(C)" f(x) = 1/sinx - 1/tan x , "(r)"4),("(D)" f(x)=(1-cos^(3)x)/( x sin 2x) , "(s)" 3/4):}

Let f(x)=x + 2|x+1|+2| x-1| . Find the values of k if f(x)=k (i) has exactly one real solution, (ii) has two negative solutions, (iii) has two solutions of opposite sign.

Let f(x)=2x+1. AA x in R , then the solution of the equation f(x)=f^(-1)(x) is

Let f(x)=x+2|x+1|+2|x-1|dot If f(x)=k has exactly one real solution, then the value of k is (a) 3 (b) 0 (c) 1 (d) 2

If |x-1|+|x-2|+|x-3|=k, x epsilon R then value of k for which given equation has exactly one solution.

Let f(x)=x+2|x+1|+x-1|dotIff(x)=k has exactly one real solution, then the value of k is 3 (b) 0 (c) 1 (d) 2

Let f (x) = (x+5)/(sqrt(x^(2) +1) ) , then the smallest integral value of k for which f (x) le k AA x in R is

Let f (x)= sin ^(-1) x-cos ^(-1) x, then the set of values of k for which of |f (x)|=k has exactly two distinct solutions is :

{:("Column-I","Column-II"),(A.f(x) = (1)/(sqrt(x -2)),p.lim_(x to 0)f(x) =1),(B. f(x) = (3x - "sin"x)/(x + "sin" x), q. lim_(x to 0)f(x) = 0),(C.f(x) = x "sin"(pi)/(x) f(0)=0,r.lim_(x to oo) f(x) = 0),(f(x) = tan^(-1) (1)/(x),s.lim_(x to 0) "does not exist"):}

If f(k - x) + f(x) = sin x , then the value of integral I = int_(0)^(k) f(x)dx is equal to