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Find the absolute maximum value and the absolute minimum value of the following function in the given interval: f(x)=x3,x∈[-2,2]

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Question

Find the absolute maximum value and the absolute minimum value of the following function in the given interval:

`f(x) =x^3, x in [-2,2]`

Sum
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Solution

f (x) =x3, x ∈ [-2, 2]

= f' (x) = 3x2

For critical points, f' (x) = 0

= 3x2 = 0 

= x = 0 ∈ [-2, 2]

Hence, for finding the absolute maximum value and the absolute minimum value, we have to evaluate f (0), f (-2) and f (2).

Now f(0) = 03, f(-2) = (-2)3 = -8 and f (2) = 23 = 8

∴ Absolute maximum value of f (x) = 8 at x = 2 and absolute minimum value of f (x) = -8 at x = -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 5.1 | Page 232

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