Khan/khan-exercises — Issue #12128: Dividing complex numbers - The answer seems wrong.
Author: KhanBugz
Created: 2012-01-25 21:43:59+00:00
State: open
Labels: chrome, win7, wrong-or-unclear

The answer says, "Finally, the fraction is simplified.
(2−1i+10i+5)/26 = (−3−11i)/26"

Shouldn't this simplify to the following:
(2−1i+10i+5)/26=(7+9i)/26

[dividing_complex_numbers.html?seed=52&problem=0](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/dividing_complex_numbers.html?seed=52&problem=0&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/dividing_complex_numbers.html?seed=52&problem=0&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5C%22.29%5C%22%2C%5C%22.38%5C%22%5D%22%2C542%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C5%5D%2C%5B%22hint-activity%22%2C%220%22%2C6%5D%2C%5B%22incorrect-activity%22%2C%22%5B%5C%22.27%5C%22%2C%5C%22.38%5C%22%5D%22%2C1002%5D%2C%5B%22incorrect-activity%22%2C%22%5B%5C%22.27%5C%22%2C%5C%22.35%5C%22%5D%22%2C291%5D%5D)

[[".29",".38"],[".27",".38"],[".27",".35"]]

Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.75 Safari/535.7

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