Question

2008 008 Ra Range of f(x) = 2008* + 2008** is

JEE/Engineering Exams

Maths

Solution

154

4.0 (1 ratings)

( A M>operatorname{GM} ) ( frac{2008^{x}+2008^{-x}}{2} geqslantleft(2008^{x} cdot 2008^{-x}right)^{y_{2}} ) ( Rightarrow frac{2008^{x}+2008^{-x}}{2} geq(1)^{1 / 2} ) ( Rightarrow frac{2008^{x}+2008^{-x} 7}{2} ) ( Rightarrow operatorname{Raye} . delta f quad f(x)=frac{2008^{x}+2008^{-x}}{2} ) is ( [1, infty) )