<PRE><B>Question 36601</B>
(3- i/5+12i) (5-12i/5-12i)

Formula:(A+B)(A-B) = A^2 - B^2 

25-144i^2   * replace i^2 by -1

25- [(144)(-1)] 

25+ 144

169 &lt;===== this is the denomenator
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now we will find the numerator

(3-i) (5-12i)

15-36i-5i+12i^2 &lt;===== replace i^2 by -1

15-41i-12

3-41i

now we will put the numerator and denomenator together 

3-41i/169 

or

3/169 - 4i/169


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