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Pls help

For z = -3 + 5i, evaluate
$z \overline{z}.$
(Note:
$\overline{z}$ denotes the conjugate of z.)

User Bwc
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2 Answers

3 votes

Answer:

34

Explanation:

Here z = -3 + 5i and the complement of this is

z-comp = -3 - 5i.

Multiplying these two quantities together, we get

9 -25i² = 9 + 25 = 34

User Andy Riordan
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Answer:


\underline{ \boxed{z\overline{z} = 34}}

Explanation:


if \: z = -3 + 5i \\then \: \overline{z} = - (3 + 5i) \\ hence \: z\overline{z} = (-3 + 5i)( - 3 - 5i) \\ z\overline{z} = 9 + 15i - 15i - {(5i)}^(2) \\ z\overline{z} = 9 - (25 ){i}^(2) \\ z\overline{z} = 9 - (25)( - 1) \\ z\overline{z} = 9 + 25 \\ \underline{ \boxed{z\overline{z} = 34}}

♨Rage♨

User Ruthless
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