Express in the form with a rational denominator.

Answer and explanation

Correct answer: A.

  1. Step 1: Multiply the numerator and denominator by the conjugate . Step 2. The denominator becomes . **Answer: . Why not the others:** : That multiplies by the same expression instead of its conjugate. : That adds the squares in the denominator instead of subtracting. : That leaves out the denominator.

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