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2 votes
Simplify (3 + 2i)(7 − 5i).

2 Answers

3 votes
(3+2i)(7-5i) = 21 - 15i + 14i + 10 = 31 - i
User Sanved
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5.9k points
5 votes
Rule needed: i^2 = -1
Standard form a + bi

(3 + 2i)(7 - 5i) FOIL
3 * 7 = 21
3 * - 5i = - 15i
2i * 7 = 14i
2i * -5i = - 10i^2 = - 10 * -1 = 10
Putting it all back together.
31 - i
User SDGator
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6.4k points