Khan/khan-exercises — Issue #5592: Trigonometry challenge - trigonometry problem doesn't accept correct solution
Author: KhanBugz
Created: 2011-11-04 20:26:31+00:00
State: open
Labels: firefox, vista

Reporter: seppo.kangas@gmail.com

the problem asks for tan^-1(-1) which corresponds to the angle 3pi/4 + n*pi. This is 135 + n*180 in degrees. 135 degrees wasn't accepted as a solution but instead the angle -45 deg was required. Either both should be accepted or then the preference for the convention of the smaller absolute value clearly stated.

[trigonometry_challenge.html?seed=96&problem=7 (inverse_trig_functions)](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trigonometry_challenge.html?seed=96&problem=7&debug)

["135 deg","-45","-45 deg"]

Mozilla/5.0 (Windows NT 6.0; rv:7.0.1) Gecko/20100101 Firefox/7.0.1

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