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Find the value of k so that the function f is continuous at the indicated point. f(x) = {๐‘˜โข๐‘ฅ2, if ๐‘ฅ โ‰ค 2, 3, if ๐‘ฅ > 2 at x = 2

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Question

Find the value 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
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Solution

f(x) = `{(kx^2", if"  x<= 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)

⇒ 3 = k(2)2

⇒ 3 = 4k

⇒ k = `3/4`

Thus, the function is continuous at x = 2 when k = `3/4`.

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

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 5 Continuity and Differentiability
Exercise 5.1 | Q 27 | Page 161

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