What is the conjugate of the complex number z = -5 + 7i?
Answer and explanation
Correct answer: A. -5 - 7i
- Step 1: The complex conjugate of z = x + iy is obtained by changing the sign of the imaginary part: z = x - iy. Step 2. For z = -5 + 7i, conjugate is -5 - 7i. Answer: -5 - 7i. Why not the others:* 5 - 7i negates real part as well; 5 + 7i only negates real part; -5 + 7i is original number.
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