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Find the maximum and minimum value, if any, of the following function given by f(x) = (2x − 1)2 + 3.

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Question

Find the maximum and minimum value, if any, of the following function given by f(x) = (2x − 1)2 + 3. 

Sum
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Solution

We have, f(x) = (2x - 1)2 + 3 for all x ∈ R.

Since, (2x - 1)2 ≥ 0

= (2x - 1)2 + 3 ≥ 3

∴ Minimum f (x) = 3, which occurs when 2x - 1 = 0 i.e, when x = `1/2`

Value of f (x) has no maximum value, because f (x) → ∞ as |x| → ∞

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Chapter 6: Application of Derivatives - Exercise 6.5 [Page 231]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 6 Application of Derivatives
Exercise 6.5 | Q 1.1 | Page 231

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