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Answer:
25 +0i
Explanation:
The conjugate of a complex number is that number with the sign of the imaginary part reversed.
For z = -3+4i, its conjugate z* is -3-4i. The product of z and z* is ...
(-3 +4i)(-3 -4i) = -3(-3 -4i) +4i(-3 -4i)
= 9 +12i -12i -16i² = 9 +16 = 25
The real part of the product is 25; the imaginary part is 0.
(-3 +4i)(-3 -4i) = 25 +0i
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You may have noticed that (z)(z*) = |z|², the sum of the squares of the real and imaginary parts. It is always a non-negative real number.