Write in the form .
Answer and explanation
Correct answer: B.
- Step 1: Multiply top and bottom by the conjugate .
- Step 2: Denominator: .
- 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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