Q23 of 36 Page 161

The minimum value of 4x + 41–x, x ∈ R, is

Here, we have to find the minimum value of 4x + 41–x

So, we use the AM – GM inequality which states that the arithmetic mean of a list of non – negative real numbers is greater than or equal to the geometric mean of the same list .i.e.







⇒ 4x + 41-x ≥ 4


Hence, the correct option is (b)

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