Quoting Post Archived Topic: It will not be bumped to the top of the forum. Topic can anyone solve these? Membername   Not a member? Sign Up Free (takes 20 seconds) Password   Forgotten your password? Post Font: Verdana Arial Black Georgia Comic Sans Impact   Size: Tiny Normal Big Huge   Color: Default Dark Red Red Orange Brown Green Olive Cyan Blue Dark Blue Indigo Black [ Check Spelling ] [ Post Preview ] [ LiveTags ] Quote: from [m]what the mong[/m] at 9:11 pm on Dec. 3, 2008[quote]cos(arccot 8) and sin[arcsin 2/3]        ------            2 thats 2 thirds divided by two points will be given out for an exact answer with work explained! hundreds of points up for grabs[/quote] FAQ Keyword Search: Post Options Favorites Manager Notify me of new replies to this topic by email Notify me of new replies to this topic by private message Original Post what the mong Posted at 9:11 pm on Dec. 3, 2008 cos(arccot 8) and sin[arcsin 2/3]        ------            2 thats 2 thirds divided by two points will be given out for an exact answer with work explained! hundreds of points up for grabs

Replies Just Waiting Here Posted at 1:20 pm on Dec. 17, 2008 Do you have the answers? cos(arccos 8) = 8 You wrote arccot... was that a typo, or is that actually what you need to solve?  I solved for arc cos. sin[arcsin 2/3]  = 1/3       ------           2 Do you know what the relationship between sin and arc sin is... or the relationship between cos and arc cos? Basically... they are inverse's of one another.  So... if... cos x = y  then... arccos y = x This being said, when you take the cos or arccos, it's just the number that you have there.  Let's take the general case. Let... cos y = x... then, by definition arccos x = y so... what is cos(arccos x)? Well... arccos x = y.  So we plug that in, and we get... cos(arccos x) = cos (y).  From above, we stated that cos y = x. Therefore... cos y = x. Using that in your first problem... the answer would just be 8 (if it was arc cos) Similar steps are taken for the second problem.  So it would just be (2/3)/2 Lukerules12 Posted at 2:51 am on Dec. 5, 2008 1? Love Today Posted at 9:19 pm on Dec. 3, 2008 I don't want to take the chance of failing you @ life. ang42490424 Posted at 9:12 pm on Dec. 3, 2008 I don't remember how to do that. I have forgotten that part of math class. xxbarbiexx Posted at 9:12 pm on Dec. 3, 2008 ??? uh no XOallixs0n Posted at 9:12 pm on Dec. 3, 2008 Aaaah. Trig <3 All 6 previous replies displayed.