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Identify discontinuities for the following function as either a jump or a removable discontinuity : f(x) =4+sinx, for x<π=3-cosx, for x>π

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Question

Identify discontinuities for the following function as either a jump or a removable discontinuity :

f(x) `{:(= 4 + sin x",",  "for"  x < pi),(= 3 - cos x",",  "for"  x > pi):}`

Sum
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Solution

`lim_(x -> pi^-) "f"(x) =  lim_(x -> pi) (4 + sin x)`

= 4 + sin π

= 4 + 0

= 4

`lim_(x -> pi^+) "f"(x) =  lim_(x -> pi) (3 - cos x)`

=3 – cos π

=3 – (– 1)

= 4

∴ `lim_(x -> pi^-) "f"(x) = lim_(x -> pi^+) "f"(x)` = 4

∴ `lim_(x -> pi) "f"(x)` exists and equals 4

But f(π) is not defined

If we define f(π) = 4, f will be continuous at x = π

∴ the discontinuity is removable.

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Chapter 8: Continuity - EXERCISE 8.1 [Page 173]

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