Khan/khan-exercises — Issue #8070: Trigonometry 1 - Trigonometry Question incorrect
Author: KhanBugz
Created: 2011-12-07 22:32:33+00:00
State: open
Labels: chrome, win7, wrong-or-unclear

AC is 7 units long
BC is 4 units long
AB is SQRT(65) units long
what is cos(Angle A)
Using CAH from SOH CAH TOA I understand that Cosθ=adjacent/hypotenuse
therefore CosA= 7/(Sqrt65)
which = (7(Sqrt65))/65
Program tells me I am incorrect

[trigonometry_1.html?seed=124&problem=cosTrig1](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trigonometry_1.html?seed=124&problem=cosTrig1&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trigonometry_1.html?seed=124&problem=cosTrig1&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%20%5C%5C%5C%22%3E%5C%5C%5C%5Cdfrac%7B7%5C%5C%5C%5Csqrt%7B65%7D%20%7D%7B65%7D%3C%2Fcode%3E%5C%22%22%2C84%5D%2C%5B%22incorrect-activity%22%2C%22%5C%22%3Ccode%20style%3D%5C%5C%5C%22display%3A%20none%3B%20%5C%5C%5C%22%3E%5C%5C%5C%5Cdfrac%7B7%5C%5C%5C%5Csqrt%7B65%7D%20%7D%7B65%7D%3C%2Fcode%3E%5C%22%22%2C258%5D%5D)

["\\dfrac{7\\sqrt{65} }{65}","\\dfrac{7\\sqrt{65} }{65}"]

Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.2 (KHTML, like Gecko) Chrome/15.0.874.121 Safari/535.2

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