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Is the function defined by f(x) = x2 − sin x + 5 continuous at x = π?

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Question

Is the function defined by f(x) = x2 − sin x + 5 continuous at x = π?

Sum
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Solution

f(x) = x2 − sin (x) + 5

If f(x) is continuous at x = π, it implies:

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

⇒ (π2 − sin (π) + 5) = (π2 − sin (π) + 5) = (π2 − sin (π) + 5)

⇒ π2 + 5 = π2 + 5 = π2 + 5

Which is true, i.e., f(x) is continuous at x = π.

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Chapter 5: Continuity and Differentiability - Exercise 5.1 [Page 160]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 5 Continuity and Differentiability
Exercise 5.1 | Q 20 | Page 160

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