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The function f(x)={{:(,x^(2)//a,0lexlt1)...

The function f(x)=`{{:(,x^(2)//a,0lexlt1),(,a,1lexltsqrt2),(,(2b^(2)-4b)/(x^(2)),sqrt2le xltoo):}` and if it is continous at x=1, `sqrt2 , then ` a and b` is equal to

A

`-2`

B

`-4`

C

`-6`

D

`-8`

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The correct Answer is:
To solve the problem, we need to ensure that the function \( f(x) \) is continuous at the points \( x = 1 \) and \( x = \sqrt{2} \). The function is defined piecewise as follows: \[ f(x) = \begin{cases} \frac{x^2}{a} & \text{if } 0 \leq x < 1 \\ a & \text{if } 1 \leq x < \sqrt{2} \\ \frac{2b^2 - 4b}{x^2} & \text{if } \sqrt{2} \leq x < \infty \end{cases} \] ### Step 1: Continuity at \( x = 1 \) To ensure continuity at \( x = 1 \), we need to check that: \[ \lim_{x \to 1^-} f(x) = f(1) \] Calculating \( \lim_{x \to 1^-} f(x) \): \[ \lim_{x \to 1^-} f(x) = \frac{1^2}{a} = \frac{1}{a} \] Calculating \( f(1) \): \[ f(1) = a \] Setting these equal for continuity: \[ \frac{1}{a} = a \] Multiplying both sides by \( a \) (assuming \( a \neq 0 \)): \[ 1 = a^2 \] Thus, we have: \[ a = \pm 1 \] ### Step 2: Continuity at \( x = \sqrt{2} \) Next, we ensure continuity at \( x = \sqrt{2} \): \[ \lim_{x \to \sqrt{2}^-} f(x) = f(\sqrt{2}) \] Calculating \( \lim_{x \to \sqrt{2}^-} f(x) \): \[ \lim_{x \to \sqrt{2}^-} f(x) = a \] Calculating \( f(\sqrt{2}) \): \[ f(\sqrt{2}) = \frac{2b^2 - 4b}{(\sqrt{2})^2} = \frac{2b^2 - 4b}{2} = b^2 - 2b \] Setting these equal for continuity: \[ a = b^2 - 2b \] ### Step 3: Solving for \( b \) Now we have two cases to consider based on the values of \( a \). #### Case 1: \( a = 1 \) Substituting \( a = 1 \) into the equation \( 1 = b^2 - 2b \): \[ 1 = b^2 - 2b \implies b^2 - 2b - 1 = 0 \] Using the quadratic formula: \[ b = \frac{-(-2) \pm \sqrt{(-2)^2 - 4 \cdot 1 \cdot (-1)}}{2 \cdot 1} = \frac{2 \pm \sqrt{4 + 4}}{2} = \frac{2 \pm 2\sqrt{2}}{2} = 1 \pm \sqrt{2} \] #### Case 2: \( a = -1 \) Substituting \( a = -1 \) into the equation \( -1 = b^2 - 2b \): \[ -1 = b^2 - 2b \implies b^2 - 2b + 1 = 0 \] This simplifies to: \[ (b - 1)^2 = 0 \implies b = 1 \] ### Final Values Thus, we have two sets of solutions: 1. For \( a = 1 \), \( b = 1 + \sqrt{2} \) or \( b = 1 - \sqrt{2} \). 2. For \( a = -1 \), \( b = 1 \). ### Summary of Results The values of \( a \) and \( b \) are: - \( a = 1 \), \( b = 1 + \sqrt{2} \) or \( b = 1 - \sqrt{2} \) - \( a = -1 \), \( b = 1 \)

To solve the problem, we need to ensure that the function \( f(x) \) is continuous at the points \( x = 1 \) and \( x = \sqrt{2} \). The function is defined piecewise as follows: \[ f(x) = \begin{cases} \frac{x^2}{a} & \text{if } 0 \leq x < 1 \\ a & \text{if } 1 \leq x < \sqrt{2} \\ \frac{2b^2 - 4b}{x^2} & \text{if } \sqrt{2} \leq x < \infty ...
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OBJECTIVE RD SHARMA ENGLISH-CONTINUITY AND DIFFERENTIABILITY-Exercise
  1. The function f(x)={{:(,x^(2)//a,0lexlt1),(,a,1lexltsqrt2),(,(2b^(2)-4b...

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  2. The function f(x) = (4-x^(2))/(4x-x^(3)) is discontinuous at

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  3. Let f(x)=|x| and g(x)=|x^3| , then (a).f(x) and g(x) both are continuo...

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  4. The function f(x)=sin^(-1)(cosx) is discontinuous at x=0 (b) continuou...

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  5. The set of points where the function f(x)=x|x| is differentiable is...

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  6. On the interval I = [-2, 2], if the function f(x) = {{:((x+1)e^(-((1)/...

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  7. If f(x)={{:(,(|x+2|)/(tan^(-1)(x+2)),x ne -2),(,2, x=-2):}, then f(x) ...

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  8. Let f(x)=(x+|x|)|x| . Then, for all x f is continuous

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  9. The set of all points where the function f(x)=sqrt(1-e^(-x^2)) is di...

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  10. The function f(x)=e^(-|x|) is continuous everywhere but not differe...

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  11. The function f(x)=[cos x] is

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  12. If f(x)=sqrt(1-sqrt(1-x^2)) , then f(x) is (a) continuous on [-1, 1] ...

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  13. If f(x) = sin ^(-1)((2x)/(1 + x^(2))) then f (x) is differentiable in ...

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  14. about to only mathematics

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  15. If f(x)=|x-a|varphi(x), where varphi(x) is continuous function, then f...

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  16. If f(x)=x^2+(x^2)/(1+x^2)+(x^2)/((1+x^2)^2)+. . . . +(x^2)/((1+x^2)^n)...

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  17. If f(x)= | log10x| then at x=1.

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  18. If f(x)=|log(e) x|,then

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  19. If f(x)=|log(e)|x||," then "f'(x) equals

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  20. Let f(x)={1/(|x|)\ \ \ \ \ for\ |x|geq1a x^2+b\ \ \ \ \ \ \ \ for\ |x|...

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  21. Let h(x)="min "{x,x^(2)} for every real number of x. Then, which one o...

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