Khan/khan-exercises — Issue #12338: Power rule - No correct answers to the question
Author: KhanBugz
Created: 2012-01-28 03:32:12+00:00
State: open
Labels: firefox, win7, wrong-or-unclear

Reporter: roman-khanacademy.org@gollent.com

There are no correct answers listed in the multiple choice. The two closest are:

−20x4−9x3+8x2−x (signs are correct but the terms have not been properly differentiated)

and

20x3+9x2−8x+1 (properly differentiated but signs are wrong

[power_rule.html?seed=23&problem=0](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/power_rule.html?seed=23&problem=0&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/power_rule.html?seed=23&problem=0&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%5C%5C%5C%22%3E20x%5E%7B3%7D%2B9x%5E%7B2%7D-8x%2B1%3C%2Fcode%3E%5C%22%22%2C49%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C25%5D%2C%5B%22hint-activity%22%2C%220%22%2C27%5D%2C%5B%22hint-activity%22%2C%220%22%2C50%5D%2C%5B%22hint-activity%22%2C%220%22%2C52%5D%2C%5B%22hint-activity%22%2C%220%22%2C53%5D%2C%5B%22hint-activity%22%2C%220%22%2C55%5D%2C%5B%22hint-activity%22%2C%220%22%2C62%5D%5D)

["20x^{3}+9x^{2}-8x+1"]

Mozilla/5.0 (Windows NT 6.1; WOW64; rv:10.0) Gecko/20100101 Firefox/10.0

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