Question 1053304
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(3+2i)(3-2i)
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<pre>
Trace attentively each my step:


(3+2i)(3-2i) = 3*3  + 3*(-2i)  + (2i)*3  + (2i)*(-2i) = 

                9   - 6i       +  6i     - {{{4*i^2}}} =   cancel -6i and 6i;  use {{{i^2}}} = -1)

                9                        - 4*(-1)      = 9 + 4 = 13.



Or  (3+2i)(3-2i)  = {{{3^2 - (2i)^2}}} = {{{9 - 4*i^2}}} = 9 -4*(-1) = 9 + 4 = 13.
</pre>

Done.