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Examine contnuity of the function f(x)...

Examine contnuity of the function `f(x) = x^(3) + 2x^(2)- 1` at `x = 1`.

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To examine the continuity of the function \( f(x) = x^3 + 2x^2 - 1 \) at \( x = 1 \), we will follow these steps: ### Step 1: Determine \( f(1) \) First, we need to evaluate the function at \( x = 1 \). \[ f(1) = 1^3 + 2(1^2) - 1 \] \[ = 1 + 2 - 1 \] \[ = 2 \] ### Step 2: Calculate the Left-Hand Limit as \( x \) approaches 1 Next, we calculate the left-hand limit of \( f(x) \) as \( x \) approaches 1. \[ \lim_{x \to 1^-} f(x) = \lim_{h \to 0} f(1 - h) = f(1 - h) \] Substituting \( 1 - h \) into the function: \[ f(1 - h) = (1 - h)^3 + 2(1 - h)^2 - 1 \] Expanding this: \[ = (1 - 3h + 3h^2 - h^3) + 2(1 - 2h + h^2) - 1 \] \[ = 1 - 3h + 3h^2 - h^3 + 2 - 4h + 2h^2 - 1 \] Combining like terms: \[ = (1 + 2 - 1) + (-3h - 4h) + (3h^2 + 2h^2) - h^3 \] \[ = 2 - 7h + 5h^2 - h^3 \] Taking the limit as \( h \to 0 \): \[ \lim_{h \to 0} (2 - 7h + 5h^2 - h^3) = 2 \] ### Step 3: Calculate the Right-Hand Limit as \( x \) approaches 1 Now, we calculate the right-hand limit of \( f(x) \) as \( x \) approaches 1. \[ \lim_{x \to 1^+} f(x) = \lim_{h \to 0} f(1 + h) = f(1 + h) \] Substituting \( 1 + h \) into the function: \[ f(1 + h) = (1 + h)^3 + 2(1 + h)^2 - 1 \] Expanding this: \[ = (1 + 3h + 3h^2 + h^3) + 2(1 + 2h + h^2) - 1 \] \[ = 1 + 3h + 3h^2 + h^3 + 2 + 4h + 2h^2 - 1 \] Combining like terms: \[ = (1 + 2 - 1) + (3h + 4h) + (3h^2 + 2h^2) + h^3 \] \[ = 2 + 7h + 5h^2 + h^3 \] Taking the limit as \( h \to 0 \): \[ \lim_{h \to 0} (2 + 7h + 5h^2 + h^3) = 2 \] ### Step 4: Compare the Limits and the Function Value Now we compare the left-hand limit, right-hand limit, and the function value at \( x = 1 \): - Left-hand limit: \( \lim_{x \to 1^-} f(x) = 2 \) - Right-hand limit: \( \lim_{x \to 1^+} f(x) = 2 \) - Function value: \( f(1) = 2 \) Since all three values are equal, we conclude that the function is continuous at \( x = 1 \). ### Conclusion The function \( f(x) = x^3 + 2x^2 - 1 \) is continuous at \( x = 1 \). ---

To examine the continuity of the function \( f(x) = x^3 + 2x^2 - 1 \) at \( x = 1 \), we will follow these steps: ### Step 1: Determine \( f(1) \) First, we need to evaluate the function at \( x = 1 \). \[ f(1) = 1^3 + 2(1^2) - 1 \] ...
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NCERT EXEMPLAR-CONTINUITY AND DIFFERENTIABILITY-Continuity And Differentiability
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  2. If f.g is continuous at x = 0 , then f and g are separately continuou...

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  3. Examine contnuity of the function f(x) = x^(3) + 2x^(2)- 1 at x = 1.

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  4. f(x)={{:(3x+5, if x ge 2),(x^(3), if x le 2):}at x = 2

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  5. f(x)={{:((1-cos2x)/(x^(2)),if x ne 0),(5, if x = 0):} at x = 0.

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  6. f(x) = {{:((2x^(2)-3x-2)/(x-2), if x ne 2), (5, if x = 2):} at x = 2.

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  7. f(x)= {{:((|x-4|)/(2(x-4)), if x ne 4),(0,if x = 4):} at x = 4.

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  8. f(x)={{:(|x|cos\ 1/x, if x ne 0),(0, if x =0):} at x = 0 .

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  9. f(x) = {{:(|x|sin\ (1)/(x-a),if x ne 0),(0, if x =a):} at x = a

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  10. f(x)={{:(e^(1//x)/(1+e^(1//x)),if x ne 0),(0,if x = 0):} at x = 0

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  11. {{:(x^(2)/2, if 0le x le 1),(2x^(2)-3x+3/2, if l lt x le 2):} at x = ...

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  12. f(x) = |x| + |x-1| at x = 1.

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  13. f(x)={{:(3x-8, if x le 5),(2k, if x gt 5) :} at x = 5

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  14. If f(x)={(2^(x+2)-16)/(4^x-16),ifx!=2k ,ifx=2i scon t inuou sa tx=2,f...

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  15. f(x) = {{:((sqrt(1+kx)-sqrt(1-kx))/(x),if -1 le x lt 0),((2x+1)/(x-1),...

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  16. f(x) = {{:((1-coskx)/(x sinx), if x ne 0),(1/2, if x = 0):} at x = 0

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  17. Prove that the function f defined by f(x) = {{:((x)/(|x|+2x^(2)), if ...

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  18. Find the values of a and b sucht that the function f defined by ...

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  19. If the function f(x) = 1/(x+2), then find the points of discountinu...

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  20. Find all point of discountinuity of the function f(t) = (1)/(t^(2)...

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