मराठी

If f(x) = ,k,{x3+x2-16x+20(x-2)2,x≠2k,x=2 is continuous at x = 2, find the value of k. - Mathematics

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प्रश्न

If f(x) = `{{:((x^3 + x^2 - 16x + 20)/(x - 2)^2",", x ≠ 2),("k"",", x = 2):}` is continuous at x = 2, find the value of k.

बेरीज
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उत्तर

Given f(2) = k.

Now, `lim_(x -> 2) "f"(x) = lim_(x -> 2^+) "f"(x)`

= `lim_(x -> 2) (x^3 + x^2 - 16x + 20)/(x - 2)^2`

= `lim_(x -> 2) ((x - 5)(x - 2)^2)/(x - 2)^2`

= `lim_(x -> 2) (x + 5)`

= 7

As f is continuous at x = 2, we have

`lim_(x -> 2) "f"(x)` = f(2)

⇒ k = 7.

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पाठ 5: Continuity And Differentiability - Solved Examples [पृष्ठ ९२]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 5 Continuity And Differentiability
Solved Examples | Q 3 | पृष्ठ ९२

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