The function in question is:
f(x) = \arccos(2x^2 - 1) - 2\arccos(x)
Given the trigonometric identity:
\arccos(2x^2 - 1) = 2\arccos(x)
We know that for x \in [0,1] :
\arccos(2x^2 - 1) = 2\arccos(x)
Therefore, for x \in [0,1] :
f(x) = \arccos(2x^2 - 1) - 2\arccos(x) = 2\arccos(x) - 2\arccos(x) = 0
B.Therefore, the function f(x) = \arccos(2x^2 - 1) - 2\arccos(x) is equal to 0 for all x in the interval [0,1] .
\boxed{f(x) = 0}