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Find the values of k so that the function f is continuous at the indicated point. ,, at xf(x)={kx2,ifx≤23,ifx>2 at x=2 - Mathematics

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Question

Find the values of k so that the function f is continuous at the indicated point.

`f(x) = {(kx^2, "," if x<= 2),(3, "," if x > 2):} " at x" = 2`

Sum

Solution

`f(x) = {(kx^2"," " if"  x le 2),(3"," " if"  "x" > 2):}`

If f(x) is continuous at x = 2, this implies:

f(2) `= lim _(x -> 2^+)  f(x) = lim_(x -> 2^-)  f(x)`

`=>` k(4) = 3 = k(4)

`=>` 3 = k(4)

`=> k = 3/4` 

That is, for the quantity `k = 3/4` this function is continuous at x = 2.

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Chapter 5: Continuity and Differentiability - Exercise 5.1 [Page 161]

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NCERT Mathematics [English] Class 12
Chapter 5 Continuity and Differentiability
Exercise 5.1 | Q 27 | Page 161

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