Simplify the complex number , where .
Answer and explanation
Correct answer: A.
.
- Step 1: Multiply numerator and denominator by the complex conjugate of the denominator, :
- Step 2: Expand the denominator: .
- Step 3: Expand the numerator: .
- Step 4: Divide by 2: .
Answer
.
Why not the others: '' computes ; '' makes an error in expanding cross terms; '' uses conjugate in the numerator.
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