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3 votes
Identify the quotient in the form a + bi.
6i/3+2i

Please show your work!

User Chrismear
by
5.6k points

2 Answers

6 votes

Answer:


(12)/(13)+(18)/(13)i

Explanation:

Multiply by the conjugate as a factor of one:


(6i)/(3+2i)=(6i)/(3+2i)*(3-2i)/(3-2i)=(18i+12)/(9+4)=(12+18i)/(13)=(12)/(13)+(18)/(13)i

User Steven Rosato
by
5.8k points
5 votes

Answer:
(12)/(13)+(18)/(13)i

The expression is in a+bi form where,

a = 12/13

b = 18/13

================================================

Work Shown:

Multiply top and bottom by 3-2i, which is the conjugate of the original denominator. This will make the denominator go from a nonreal complex number to a purely real number.


(6i)/(3+2i)\\\\\\(6i(3-2i))/((3+2i)(3-2i))\\\\\\(18i-12i^2)/((3)^2-(2i)^2)\\\\\\(18i-12i^2)/(9-4i^2)\\\\\\(18i-12(-1))/(9-4(-1))\\\\\\(18i+12)/(9+4)\\\\\\(12+18i)/(13)\\\\\\(12)/(13)+(18)/(13)i\\\\\\

The last expression is in a+bi form where a = 12/13 and b = 18/13

Keep in mind that
i = √(-1) has both sides square to
i^2 = -1. Also, I'm using the difference of squares rule to go from
(3+2i)(3-2i) to
(3)^2 - (2i)^2.

User Slott
by
6.1k points