Recent content by caharris

[edit:]My teacher did it where she got cos(x)= \frac{1}{2}, but when I tried it I got cos(x)= \frac{-1}{2}. This is what she had (btw, she was kind of out of it, so she may have done something wrong): 2cos2(x)+3cos(x)-2=0 (cos(x)+2)(cos(x)- \frac{-1}{2} (cos(x)+2)(2cos(x)-1)=0 cos(x)=-2 cos(x)=...

Well, I know my original answer is wrong. I forgot the square when I changed Sin2(x) into 1-Cos2(x). (I had put 1-Cos(x). Ugh.) [edit:] So I got \frac{Cos(x)}{Sin^2(x)} = \frac{2}{3} but I don't know how to get that into a single identity to get a degree.

Wait wait I see what I had done. I turned cos2(x) into cos2-sin2 using the double angle formula. So yeah you're correct. [edit:]Haha I thought I was about cry because this problem took me forever

Gosh, I feel so dumb. "Solve cos2(x)+3cos(x)-1=0" I messed up that whole problem... Give me a few minutes.

Well it's cos2(x), not cos2(x). Double angle formula. (Sorry that I didn't make that clear.) Same with sin as well.

Yeah, I'm checking over my homework, and I'm just making sure everything turns out correct. "Solve cos2(x)+3cos(x)-1=0 for 0deg\leqx\leq360deg" and I got an answer of 315deg. I'm questioning whether that part is correct (which, as you say, it is) and when I somehow went from...

Another quick question: can you divide out a Cos(x) from Cos^{2}(x) - Sin^{2}(x) + 3Cos(x) = 1 and get Cos(x) - \frac{Sin^{2}(x)}{Cos(x)} + 3 = Sec(x) ? Or would it make it Cos(x) - \frac{Sin^{2}(x)}{Cos(x)} + 2Cos(x) = Sec(x) ?

Ahh, thank you so much! I wasn't that far off :-p All of your help was invaluable! Thank you all again.

Okay, I'm thinking this is wrong, but here's what I did. I plugged the formula into Mathematica and it gave me Cos2(x)(1-Sin2(x)). I figured out that, via moving the Sin2(x)+Cos2(x)=1 formula around that 1-Sin2(x) is equal to -Cos2(x). I plugged this into the original formula (that Mathematica...

Gotcha, should have recognized that. I'm tired, so I probably just missed it. Thank you for your help! Did you get this by factoring out a Cos2?

Are you saying that the left changes into the right side of the equation, or the cos2(x) from the original equation turns into the right side of your equation? @MysticDude No, I'm still working on it. I'm going to try micromass' suggestion now.

This is what I got, to be honest. Took me four hours, but I got it! Thank you guys so much!

Homework Statement Verify that \frac{Csc(x)}{Cot(x)+Tan(x)}=Cos(x) is an identity. Homework Equations All of the trigonometric identities. Sin^{2}+Cos^{2}=1; tan^{2}+1=Sec^{2}; 1+Cot^{2}=Csc^{2}; etc. The Attempt at a Solution I've literally written about five pages worth trying...