Khan/khan-exercises — Issue #13100: Unit circle - Missing Y
Author: KhanBugz
Created: 2012-02-05 07:30:38+00:00
State: open
Labels: firefox, wrong-or-unclear, xp

In this problem, when you spin around to 3pi, the y coordinate dissapears, leaving an x of -1. However, the x is NOT labled, so this leads a student to assume this is the value needed. Since -1/1 is -1, I entered that, and got it wrong. Then I took a second look and realized I was NOT being given an ordered pair. It would be better if the X and Y were NOT on points on the circle, but were a static ordered pair position that changed values. Then the person would be tested on if they could translate an ordered pair into a trig function.

[unit_circle.html?seed=130&problem=radians](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/unit_circle.html?seed=130&problem=radians&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/unit_circle.html?seed=130&problem=radians&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22-1%5C%22%22%2C36%5D%2C%5B%22correct-activity%22%2C%22%5C%220%5C%22%22%2C12%5D%5D)

["-1","0"]

Mozilla/5.0 (Windows NT 5.1; rv:9.0.1) Gecko/20100101 Firefox/9.0.1

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