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Evaluate: limx→124x2-12x -1

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Question

Evaluate: `lim_(x -> 1/2) (4x^2 - 1)/(2x  - 1)`

Sum
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Solution

Given that `lim_(x -> 1/2) (4x^2 - 1)/(2x  - 1)`

= `lim_(x -> 1/2) ((2x)^2 - (1)^2)/(2x - 1)`

= `lim_(x -> 1/2) ((2x + 1)(2x - 1))/(2x - 1)`

= `lim_(x -> 1/2) (2x + 1)`

Taking limit, we have

= `2 xx 1/2 + 1`

= 1 + 1

= 2.

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Chapter 13: Limits and Derivatives - Exercise [Page 239]

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NCERT Exemplar Mathematics Exemplar [English] Class 11
Chapter 13 Limits and Derivatives
Exercise | Q 2 | Page 239

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