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Find 'a' and 'b' if the function : f(x...

Find 'a' and 'b' if the function :
`f(x)={{:((sinx)/(x)" , "-2lexlt0),(a.2^(x)" , "0lexle1),(b+x", "1ltxle2):}`
is a continuous function on [-2, 2].

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To find the values of 'a' and 'b' such that the function \[ f(x) = \begin{cases} \frac{\sin x}{x} & \text{if } -2 < x < 0 \\ a \cdot 2^x & \text{if } 0 \leq x \leq 1 \\ b + x & \text{if } 1 < x \leq 2 \end{cases} \] is continuous on the interval \([-2, 2]\), we need to ensure that the function is continuous at the points where the definition of the function changes, specifically at \(x = 0\) and \(x = 1\). ### Step 1: Continuity at \(x = 0\) For the function to be continuous at \(x = 0\), we need: \[ \lim_{x \to 0^-} f(x) = f(0) = \lim_{x \to 0^+} f(x) \] Calculating the left-hand limit: \[ \lim_{x \to 0^-} f(x) = \lim_{x \to 0} \frac{\sin x}{x} = 1 \] Calculating the value of the function at \(x = 0\): \[ f(0) = a \cdot 2^0 = a \] Setting the left-hand limit equal to the function value: \[ 1 = a \] ### Step 2: Continuity at \(x = 1\) For the function to be continuous at \(x = 1\), we need: \[ \lim_{x \to 1^-} f(x) = f(1) = \lim_{x \to 1^+} f(x) \] Calculating the left-hand limit: \[ \lim_{x \to 1^-} f(x) = a \cdot 2^1 = 2a \] Calculating the value of the function at \(x = 1\): \[ f(1) = b + 1 \] Setting the left-hand limit equal to the function value: \[ 2a = b + 1 \] ### Step 3: Substitute the value of 'a' From Step 1, we found that \(a = 1\). Substituting this value into the equation from Step 2: \[ 2(1) = b + 1 \] This simplifies to: \[ 2 = b + 1 \implies b = 1 \] ### Conclusion The values of \(a\) and \(b\) are: \[ a = 1, \quad b = 1 \]
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MODERN PUBLICATION-CONTINUITY AND DIFFERENTIABILITY-EXERCISE 5(a) (LONG ANSWER TYPE QUESTIONS (I))
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  2. Determine the constants 'a' and 'b' so that the function 'f' defined b...

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  6. Find 'a' and 'b' if the function : f(x)={{:((sinx)/(x)" , "-2lexlt0)...

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  7. Determine the values of 'a' and 'b' such that the following function i...

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  8. Let f(x)={{:((1-sin^(3)x)/(3cos^(2)x),"if "x lt(pi)/(2)),(a,"if "x=(pi...

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  9. If the following function f (x) is continuous at x=0 , find the values...

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  10. If f(x) {:(=x^(2)+ax+b", if "0 le x lt 2 ),(= 3x+2", i...

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  11. Find all the points of discontinuity of the function 'f' defined by : ...

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  12. Find all points of discontinuity of f, where f is defined byf(x)={|x|...

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  13. Find all points of discontinuity of f, where f is defined byf(x)={2x+...

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  14. Show that the function defined by f(x)" "=" "s in" "(x^2) is a cont...

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  15. Show that the function defined by f(x)=cos(x^2)is a continuous functi...

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  16. Show that the function defined by f(x) = | cos x |is a continuous fun...

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  17. Show that the function 'f' given by : f(x)=|x|+|x-1|,x inR is cont...

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  18. Discuss the continuity of the function of given by f(x)=+x-1|+|x-2|a t...

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  19. Find the points of discontinuity, if any, of the following function...

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  20. Discuss continuity of |x|.

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