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MacyBeee
Apr 2, 2013, 04:36 PM
csc^(4)(θ)-cot^(4)(θ)=2csc^(2)(θ)-1
I've tried this problem at least 5 different times and the only answer I've gotten is cos^2(θ)+cot^2(θ). It's so frustrating. I got all of the other 14 questions in the homework but I can't get this one. I tried it so many times so I wouldn't have to ask for help, but I just can't figure it out. I also contacted one of my friends in the class, but she didn't know it either. Any help is greatly appreciated! Thanks ahead of time!

ebaines
Apr 3, 2013, 05:58 AM
What have you tried? I suggest converting the cosecant and cotangent fuctions to their sine and cosine equivalents, then simpify. The only trick is that if you get an expression like 1 - cos^4x note use the fact that it's the difference of two squares, so 1- cos^4x = (1- cos^2x)(1+cos^2x), and then you should recognize that 1-cos^2x = sin^2x. OK, that's enough hints - hope this helps.