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Rolle's theorem is not applicable to the...

Rolle's theorem is not applicable to the function `f(x)=|x|"for"-2 le x le2` becase

A

f is continuus on [ -2,2]

B

f is not derivable at x=0

C

`f(-2)=f(x)`

D

f is not a constant function

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The correct Answer is:
To determine why Rolle's theorem is not applicable to the function \( f(x) = |x| \) for the interval \([-2, 2]\), we need to check the conditions required for Rolle's theorem to hold. ### Step-by-Step Solution: 1. **Understanding Rolle's Theorem**: - Rolle's theorem states that if a function \( f \) is continuous on the closed interval \([a, b]\) and differentiable on the open interval \((a, b)\), and \( f(a) = f(b) \), then there exists at least one \( c \) in \((a, b)\) such that \( f'(c) = 0 \). 2. **Check Continuity**: - The function \( f(x) = |x| \) is continuous everywhere, including the interval \([-2, 2]\). - Specifically, at \( x = 0 \), we can check the limits: - Left-hand limit: \( \lim_{x \to 0^-} f(x) = \lim_{x \to 0^-} (-x) = 0 \) - Right-hand limit: \( \lim_{x \to 0^+} f(x) = \lim_{x \to 0^+} x = 0 \) - Since both limits are equal and \( f(0) = 0 \), \( f(x) \) is continuous at \( x = 0 \). 3. **Check Differentiability**: - To apply Rolle's theorem, we need to check if \( f(x) \) is differentiable on the open interval \((-2, 2)\). - The derivative from the left at \( x = 0 \): \[ f'(0^-) = \lim_{x \to 0^-} \frac{f(x) - f(0)}{x - 0} = \lim_{x \to 0^-} \frac{-x - 0}{x} = \lim_{x \to 0^-} -1 = -1 \] - The derivative from the right at \( x = 0 \): \[ f'(0^+) = \lim_{x \to 0^+} \frac{f(x) - f(0)}{x - 0} = \lim_{x \to 0^+} \frac{x - 0}{x} = \lim_{x \to 0^+} 1 = 1 \] - Since \( f'(0^-) \neq f'(0^+) \), the function \( f(x) \) is not differentiable at \( x = 0 \). 4. **Conclusion**: - Since \( f(x) = |x| \) is not differentiable at \( x = 0 \), it fails the differentiability condition of Rolle's theorem. Therefore, Rolle's theorem is not applicable to the function \( f(x) = |x| \) on the interval \([-2, 2]\). ### Final Answer: Rolle's theorem is not applicable to the function \( f(x) = |x| \) for the interval \([-2, 2]\) because the function is not differentiable at \( x = 0 \).

To determine why Rolle's theorem is not applicable to the function \( f(x) = |x| \) for the interval \([-2, 2]\), we need to check the conditions required for Rolle's theorem to hold. ### Step-by-Step Solution: 1. **Understanding Rolle's Theorem**: - Rolle's theorem states that if a function \( f \) is continuous on the closed interval \([a, b]\) and differentiable on the open interval \((a, b)\), and \( f(a) = f(b) \), then there exists at least one \( c \) in \((a, b)\) such that \( f'(c) = 0 \). 2. **Check Continuity**: ...
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OBJECTIVE RD SHARMA ENGLISH-MEAN VALUE THEOREMS-Exercise
  1. Rolle's theorem is not applicable to the function f(x)=|x|"for"-2 le x...

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  2. Let a and b be two distinct roots of a polynomial equation f(x) =0 The...

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  3. If 2a+3b+6c=0, then prove that at least one root of the equation a x^2...

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  4. Let f(x)a n dg(x) be two functions which are defined and differentiabl...

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  5. Let f be differentiable for all x , If f(1)=-2a n df^(prime)(x)geq2 fo...

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  6. If the function f(x)=x^3-6x^2+a x+b defined on [1,3] satisfies Rolles ...

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  7. Let (a0)/(n+1)+(a1)/n+(a2)/(n-1)++(a(n-1))/2+an=0. Show that there e...

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  8. The number of values of k for which the equation x^3-3x+k=0 has two di...

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  9. if f(x)=(x -4) (x-5) (x-6) (x-7) then, (A) f'(x) =0 has four roots (...

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  10. Let fa n dg be differentiable on [0,1] such that f(0)=2,g(0),f(1)=6a n...

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  11. If the equation a(n)x^(n)+a(n-1)x^(n-1)+..+a(1)x=0, a(1)!=0, n ge2, ha...

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  12. The equation x log x = 3-x has, in the interval (1,3) :

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  13. If f(x) and g(x) ar edifferentiable function for 0lex le1 such that f(...

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  14. If alpha beta( alpha lt beta) are two distinct roots of the equation. ...

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  15. If (x) is a function given by f(x) = |{:(sinx , sin a, sin b),(cosx,c...

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  16. The value of c in Lagrange's theorem for the functin f(x)=log sin x in...

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  17. n is a positive integer. If the value of c presecribed in Rolle's th...

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  18. The distance travelled by a particle upto tiem x is given by f(x)=x^(...

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  19. The number of real roots of the equation e^(x-1)+x-2=0 is 1 (b) 2 (...

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  20. If the polynomial equation an x^n + a(n-1) x^(n-1) + a(n-2) x^(n-2) + ...

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  21. If 4a+2b+c=0 , then the equation 3ax^(2)+2bx+c=0 has at least one rea...

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