Write in the form .

Answer and explanation

Correct answer: B.

  1. Step 1: Multiply top and bottom by the conjugate .
  2. Step 2: Denominator: .
  3. Step 3: Numerator: .
Answer
.
Why not the others: : is what you get for , so the conjugate has the wrong sign. : forgets to multiply the numerator by 6. : swaps the two coefficients.

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