f(x+2) = f(x) + f(x+1)
f(11) = 91
Let f(12) = a
f(13) = 91 + a
f(14) = 91 + 2a
f(15) = 182 + 3a.
This is also equal to 617.
182 + 3a = 617 => a = 145
f(10) = f(12) - f(11) = 145 - 91 = 54.
Let A be the set of 30 students of class XII in a school. Let f : A -> N, N is a set of natural numbers such that function f(x) = Roll Number of student x.
Give reasons to support your answer to (i).
Find the domain of the function \( f(x) = \cos^{-1}(x^2 - 4) \).