List-I (Types of adaptation) | List-II (Examples) | ||
1 | Biochemical adaptation | p | Desert lizards |
2 | Behavioural adaptation | q | Deep sea fishes |
3 | Physiological adaptation | r | Opuntia |
4 | Morphological adaptation | s | Kangaroo rats |
Given, the function \( f(x) = \frac{a^x + a^{-x}}{2} \) (\( a > 2 \)), then \( f(x+y) + f(x-y) \) is equal to