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Let f (x) =-1 +|x-2| and g (x) =1-|x| th...

Let `f (x) =-1 +|x-2| and g (x) =1-|x|` then set of all possible value (s) of for which (fog) (x) is discontinuous is:

A

`{0,1,2}`

B

`{0,2}`

C

`{0}`

D

an empty set

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AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the set of all possible values for which the composition \( (f \circ g)(x) \) is discontinuous. We start with the given functions: 1. \( f(x) = -1 + |x - 2| \) 2. \( g(x) = 1 - |x| \) ### Step 1: Find \( g(x) \) The function \( g(x) = 1 - |x| \) is defined for all real numbers \( x \). It is a piecewise function: - For \( x \geq 0 \): \( g(x) = 1 - x \) - For \( x < 0 \): \( g(x) = 1 + x \) ### Step 2: Find \( f(g(x)) \) Now we need to substitute \( g(x) \) into \( f(x) \): \[ f(g(x)) = f(1 - |x|) = -1 + |(1 - |x|) - 2| \] This simplifies to: \[ f(g(x)) = -1 + |1 - |x| - 2| = -1 + | -1 - |x| | = -1 + | -1 - |x| | \] ### Step 3: Simplify \( f(g(x)) \) Now we need to analyze \( | -1 - |x| | \): - For \( |x| \geq 1 \): \( -1 - |x| \) is negative, so \( | -1 - |x| | = -(-1 - |x|) = 1 + |x| \) - For \( |x| < 1 \): \( -1 - |x| \) is negative, so \( | -1 - |x| | = -(-1 - |x|) = 1 + |x| \) Thus, we can write: \[ f(g(x)) = -1 + (1 + |x|) = |x| \] ### Step 4: Analyze the continuity of \( f(g(x)) \) The function \( f(g(x)) = |x| \) is continuous everywhere on the real line. ### Conclusion Since \( f(g(x)) = |x| \) is continuous for all \( x \), there are no points of discontinuity. ### Final Answer The set of all possible values for which \( (f \circ g)(x) \) is discontinuous is the empty set: \[ \text{Set of discontinuous points} = \emptyset \]
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VIKAS GUPTA (BLACK BOOK) ENGLISH-CONTINUITY, DIFFERENTIABILITY AND DIFFERENTIATION-EXERCISE (SUBJECTIVE TYPE PROBLEMS)
  1. Let f (x) =-1 +|x-2| and g (x) =1-|x| then set of all possible value (...

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  2. Let f (x)= {{:(ax (x-1)+b,,, x lt 1),( x+2,,, 1 le x le 3),(px ^(2) +q...

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  3. If y= sin (8 sin ^(-1) x ) then (1-x ^(2)) (d^(2)y)/(dx ^(2))-x (dy)/...

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  4. If y ^(2) =4ax, then (d^(2) y)/(dx ^(2))=(ka ^(2))/( y ^(3)), where k ...

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  5. The number of values of x , x ∈ [-2,3] where f (x) =[x ^(2)] sin (pix)...

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  6. If f (x) is continous and differentiable in [-3,9] and f'(x) in [-2,8]...

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  7. In f (x)= [{:(cos x ^(2),, x lt 0), ( sin x ^(3) -|x ^(3)-1|,, x ge 0)...

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  8. Consider f(x) =x^(2)+ax+3 and g(x) =x+band F(x) = lim( n to oo) (f...

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  9. Let f (x)= {{:(2-x"," , -3 le x le 0),( x-2"," , 0 lt x lt 4):} Then f...

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  10. If f (x) +2 f (1-x) =x ^(2) +2 AA x in R and f (x) is a differentiable...

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  11. Let f (x)= signum (x) and g (x) =x (x ^(2) -10x+21), then the number o...

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  12. If (d^(2))/(d x ^(2))((sin ^(4)x+ sin ^(2)x+1)/(sin ^(2)x + si n x+1))...

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  13. f (x) =a cos (pix)+b, f'((1)/(2))=pi and int (1//2)^(3//2) f (x) dx =2...

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  14. Let alpha (x) = f(x) -f (2x) and beta (x) =f (x) -f (4x) and alpha '(1...

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  15. Let f (x) =-4.e ^((1-x)/(2))+ (x ^(3))/(3 ) + (x ^(2))/(2)+ x+1 and g ...

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  16. If y=e^(2 sin ^(-1)x) then |((x ^(2) -1) y ^('') +xy')/(y)| is equal t...

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  17. Let f be continuous function on [0,oo) such that lim (x to oo) (f(x)+ ...

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  18. Let f (x)=x+ (x ^(2))/(2 )+ (x ^(3))/(3 )+ (x ^(4))/(4 ) +(x ^(5))/(5)...

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  19. In f (x)= [{:(cos x ^(2),, x lt 0), ( sin x ^(3) -|x ^(3)-1|,, x ge 0)...

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  20. Let f :R to R be a differentiable function satisfying: f (xy) =(f(x)...

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  21. For the curve sinx+siny=1 lying in first quadrant. If underset(xrarr0...

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