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F(x) = ,if,if{3x+5,if x≥2x2,if x<2 at x = 2 - Mathematics

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Question

f(x) = `{{:(3x + 5",", "if"  x ≥ 2),(x^2",", "if"  x < 2):}` at x = 2

Sum
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Solution

We have, f(x) = `{{:(3x + 5",", "if"  x ≥ 2),(x^2",", "if"  x < 2):}` at x = 2.

At x = 2

R.H.L. = `lim_(x -> 2^+) (3x + 5)`

= `lim_("h" -> 0) [3(2 + "h") + 5]` = 11

And L.H.L. = `lim_(x -> 2^-) x^2`

= `lim_("h" -> 0) (2 - "h")^2` = 4

Since, L.H.L. ≠ R.H.L. at x = 2

So, f(x) is discontinuous at x = 2.

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Chapter 5: Continuity And Differentiability - Exercise [Page 107]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 5 Continuity And Differentiability
Exercise | Q 2 | Page 107

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