We start off with the expression (1+i)(2−i)(3+i)
Now, let's expand and simplify the bottom, we get (1+i)(7−i)
Now let's start the rationalization process. Multiply the top and bottom by the conjugate of the denominator, and we get
(1+i)(7−i)⋅(7+i)(7+i)=6+8i50
Dividing top and bottom by 2 and canceling out the 2, we get
125(3+4i) which is our final answer.
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