MCQ
$(z + a)(\bar z + a)$, where $a$ is real, is equivalent to
- A$|z - a|$
- B${z^2} + {a^2}$
- ✓$|z + a{|^2}$
- DNone of these
✓
Answer
Correct option: C.
$|z + a{|^2}$
c
(c) As we know if $a$ is real, then $a = \overline a $
$(z + a)(\overline z + a) = (z + a)(\overline z + \overline a ) = (z + a)(\overline {z + a} )$ $ = |z + a{|^2}$
(c) As we know if $a$ is real, then $a = \overline a $
$(z + a)(\overline z + a) = (z + a)(\overline z + \overline a ) = (z + a)(\overline {z + a} )$ $ = |z + a{|^2}$
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