If $ f(x)=\frac{2^{x}+2^{-x}}{2} $, then $ f(x+y) . f(x-y) $ is equal to

$ \frac{1}{2}[f(x+y) \cdot f(x-y)] $

JEE MATHEMATICS MCQ: FUNCTIONS

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Application +4 | -1

f(x)=\frac{2^{x}+2^{-x}}{2}

, then

f(x+y) . f(x-y)

is equal to

View answer and explanation

Correct option: B

\frac{1}{2}[f(2 x)+f(2 y)]

Option B (

\frac{1}{2}[f(2 x)+f(2 y)]

) is correct because it is the simplified form of the product f(x+y) . f(x-y) using the given function definition.

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