Let , . The inverse function has rule and domain:

Answer and explanation

Correct answer: B. with domain

  1. Step 1: Complete the square: . On the range is .
  2. Step 2: Swap and solve: , so .
  3. Step 3: Since the original domain has , take the negative root: , with domain equal to the range of , .
Answer
on .
Why not the others: The positive root gives outputs , outside the original domain; is the range of the inverse, not its domain; misreads the completed square.

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