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Examine the continuity of the function f(x) = 2x^2 – 1 at x = 3. - Mathematics

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Question

Examine the continuity of the function f(x) = 2x2 – 1 at x = 3.

Sum
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Solution

f(x) = 2x2 – 1

At x = 3,

`lim_(x -> 3)` f(x) = `lim_(x -> 3)` (2x2 – 1)

= 2 × (3)2 – 1

= 2 × 9 – 1

= 18 – 1

= 17

f(3) = 2 × (3)2 – 1 = 17

`lim_(x -> 3)` f(x) = f(3)

Hence, the function is continuous at x = 3.

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Chapter 5: Continuity and Differentiability - Exercise 5.1 [Page 159]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 5 Continuity and Differentiability
Exercise 5.1 | Q 2 | Page 159

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