Khan/khan-exercises — Issue #10726: Trigonometry 1 - answer is wrong
Author: KhanBugz
Created: 2012-01-09 08:23:53+00:00
State: open
Labels: ie8, wrong-or-unclear, xp

Reporter: narddog18501@gmail.com

the question is, what is cos(angle ABC) and the answer is cos(angle ABC) = 9/(9radical2), even the solution shows this, then after the solution shows the final answer is radical2/2. I repeat, the question is what is cos(angleABC)

[trigonometry_1.html?seed=29&problem=cosTrig1](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trigonometry_1.html?seed=29&problem=cosTrig1&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trigonometry_1.html?seed=29&problem=cosTrig1&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22None%20of%20the%20above.%5C%22%22%2C23%5D%2C%5B%22hint-activity%22%2C%220%22%2C1%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%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%2C6%5D%2C%5B%22hint-activity%22%2C%220%22%2C7%5D%5D)

["None of the above."]

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