If , what is ?
Answer and explanation
Correct answer: D. 169
- Step 1: (a + bi)(a - bi) = a^2 + b^2, because i^2 = -1.
- Step 2: 5^2 + 12^2 = 169.
Answer
169.
Why not the others: The product of a complex number and its conjugate is the squared modulus, a positive real number.
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