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Find the local maxima and local minima, if any, of the following function. Find also the local maximum and the local minimum values, as the case may be: g(x)=1x2+2

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Question

Find the local maxima and local minima, if any, of the following function. Find also the local maximum and the local minimum values, as the case may be:

`g(x) = 1/(x^2 + 2)`

Sum
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Solution

Given, `g (x) = 1/ (x^2 + 2)`

= `g' (x) = (-2x)/(x^2 + 2)^2`

For critical points, let g' (x) = 0

= `(-2x)/(x^2 + 2)^2 = 0`

x = 0                                 ....(∵ x2 + 2 ≠ 0)

`g'' (x) = (6x^2 - 4)/(x^2 + 2)^3;  g'' (0) = (-4)/8 <0`

∴ g has a local maximum at x = 0 and local

maximum value is `g (0) = 1/ (0 + 2) = 1/2`

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Chapter 6: Application of Derivatives - Exercise 6.5 [Page 232]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 6 Application of Derivatives
Exercise 6.5 | Q 3.7 | Page 232

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