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For z = 2 + 3i verify the following: zz¯ = |z|2 - Mathematics and Statistics

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Question

For z = 2 + 3i verify the following:

`"z"bar("z")` = |z|2

Sum
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Solution

z = 2 + 3i

∴ `bar("z")` = 2 – 3i

and |z| = `sqrt(2^2 + 3^2)`

= `sqrt(4 + 9)`

= `sqrt(13)`

Also, `"z".bar("z") = (2 + 3"i").(2 - 3"i")`

= 4 – 9i2

= 4 + 9 ...[∵ i2 = – 1]

∴ `"z".bar("z")` = 13 = |z|2

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Chapter 1: Complex Numbers - Exercise 1.3 [Page 15]

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