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Question

What is the domain restriction on the inverse of the function below?

          

The domain only includes numbers where the following is true.

    

(Answer with an integer.)

Answer 1

Solve the equation for x ... (x-3)^2-6-y=0 finding that x= 3+/- sqrt(6+y) ... for x to be a real number, 6+y>=0 or y>= -6. This requires that (x-3)^2-6>=-6. Solve for x and find that it must be >=3.