How do you find the product of each complex number #–2i# and its conjugate?

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Answer 1 · 2017-02-23T09:32:33

Product of complex number #-2i# and its conjugate is #4#.

Complex conjugate of a complex number #a+ib# is #a-ib# and that of #a-ib# is #a+ib#.

Hence, as #-2i# can be written as #0-2i#,

its complex conjugate is #0+2i# or #2i#

Hence, their product is

#-2ixx2i#

= #-4i^2#

= #-4xx-1#

= #4#