Acertain function f satisfies the equation f(x)+2*f(6-x) = x for all r...
Solution:
Given,
f(x) * 2*f(6-x) = x
Let's put x = 1,
f(1) * 2*f(5) = 1
Now, let's put x = 5,
f(5) * 2*f(1) = 5
Multiplying both equations, we get,
[f(1) * 2*f(5)] * [f(5) * 2*f(1)] = 1 * 5
4*f(1)^2 * f(5)^2 = 5
f(1)^2 * f(5)^2 = 5/4
Now, let's put x = 4,
f(4) * 2*f(2) = 4
f(2) = 2*f(4)/4 = f(4)/2
Now, let's put x = 2,
f(2) * 2*f(4) = 2
f(4) = f(2)*2/4 = f(2)/2
Substituting f(4) and f(2) in terms of f(1), we get,
f(5) = f(1)/2
f(4) = f(1)/4
Substituting these values in f(1)^2 * f(5)^2 = 5/4, we get,
f(1)^2 * (f(1)/2)^2 = 5/4
f(1)^4 = 5/4 * 4 = 5
Taking square root,
f(1)^2 = √5
Since f(1) is a real number,
f(1) = ±√5
But f(1) cannot be negative, as f(x) is a function.
Therefore,
f(1) = √5
Hence, the correct option is A.