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You are not logged in. #1 20081123 21:23:49
cos(x  y)Prove that if and , then Last edited by tony123 (20081123 21:30:46) #2 20081124 10:23:59#3 20081124 10:27:04
Re: cos(x  y)By inspection, Last edited by Daniel123 (20081124 10:27:22) #4 20081124 10:49:28#6 20081125 12:50:06
Re: cos(x  y)By the way, you also need the condition to ensure that and are not both .#7 20100123 14:58:56
Re: cos(x  y)I know very well this expression.I am studying this function in school.I like your work.Thanks for share this information. #8 20100906 23:17:29
Re: cos(x  y)cosx +cosy=a #9 20100917 20:54:26
Re: cos(x  y)hello JaneFairfax i think that you are intresested in trigo. 