Consider cos−1(2x−1) Now we know that the domain of cos−1 is [−1,1] Hence −1≤2x−1<1 as if cos−1(2x−1) becomes 0 then f(x) will not be defined 0≤x<1 x∈[0,1)
Now consider log2x3 log2x3 =log3log2x Now domain of log cannot be less than 0, and log2x≠0 Hence x∈[0,∞)−{12} Hence domain of f(x) is →x∈[0,1)−{12}