Irrational functions are generally multilevel composite functions, which are composed of power functions and other functions or composite functions. It is related to power function, which is a special convex function.
All irrational functions constitute the so-called irrational function domain, and the common methods for finding the irrational function domain are:
1, directly solved by monotonicity and domain of function.
2. The range problem of quadratic function in a given interval.
3. Explore with basic inequalities.
4. Using trigonometric substitution, it is transformed into the range problem of trigonometric function in a specific interval.