Khan/khan-exercises — Issue #9805: Trig identities 1 - Answer is wrong or shown unclear
Author: KhanBugz
Created: 2011-12-29 18:06:26+00:00
State: open
Labels: ie8, ie9, win7, wrong-or-unclear

In the question; csc(x)=root(2), what is the cos(x), the answer is wrong because the sin(x) is calculated wrong. It says if the csc(x)=root(2), the
sin(x)=root(2)/2. I calculated this several times and the answer I always got was sin=1/root(2).

I did the same calculation for another problem where my final answer was correct, so either this or the other problem must have the wrong answer. If the answer is still right, it is not clearly shown how the answer
sin(x)=root(2)/2 is gained as the calculation contradicts the caculations shown in the videos. Hope this was explained well!

[trig_identities_1.html?seed=128&problem=0](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trig_identities_1.html?seed=128&problem=0&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/trig_identities_1.html?seed=128&problem=0&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%22None%20of%20the%20above.%5C%22%22%2C77%5D%2C%5B%22hint-activity%22%2C%220%22%2C2%5D%2C%5B%22hint-activity%22%2C%220%22%2C17%5D%5D)

["None of the above."]

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