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How to find the inverse?

Example 1. Let (Assume the function is one-to-one function.) Find f-1(x). First we set and solve for x. We see and raise the exponents to 4 both sides yields, Finally, we write for (The reason we restrict is to make f-1 a one-to one function, otherwise f-1 will not have an inverse.) Let's verify this inverse by following two methods.
Method 1. (Checking f(g(x))=g(f(x))=x).

You could use the following Maple commands to check your answer:

f:=x -> 2*x^(1/4);

g:=x -> (x/2)^4;

simplify(f(g(x)));

simplify(g(f(x)));

Method 2. Check if the graphs are symmetric to y=x.

f:= x -> 2*x^(1/4);

g:=x ->  (x/2)^4;

plot({f(x),g(x),x},x=0..10,y=0..10, scaling=constrained);

You should get something like this .

Example 2. Let for This function is one-to-one function if why?). Find f-1(x). First we set and solve for x. Take the square root both sides, yieds, Finaly, we write Can you use two methods mentioned above to verify indeed f-1 is the inverse of f?