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 11 months ago
Can someone help me solve this?
cos(x^2+45)+tan(4x+90) = sin(3x+120)
A step by step would be great.
 11 months ago
Can someone help me solve this? cos(x^2+45)+tan(4x+90) = sin(3x+120) A step by step would be great.

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xlegendx
 11 months ago
Best ResponseYou've already chosen the best response.0by solving do you mean proving?

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3What methods have been discussed?

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3We are solving for x not proving this. This isn't an identity.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3Or does it say to disprove or prove?

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1Ah yes, my bad. It says solve.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3Can you tell me what methods in class have been discussed?

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1None, this is from a book with only problems I picked up at barnes and noble. We haven't done this and wont do it for another year or two. I've had no problems with the book up to this point.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3can you tell me what methods the book has discussed?

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1None. It's a book of only problems. It starts from Geometry and works it's way up in problems.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3Name of book please

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1Math Review for the High School Classroom

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1I looked for it online and can't find it.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3I didn't see the book. :( So there are no examples?

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1No examples, just questions. :c How did you learn it?

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3Honestly, I don't know without seeing some example or them mentioning some method they want to use.

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1Ah, okay. Thanks, anyway. :)

shamil98
 11 months ago
Best ResponseYou've already chosen the best response.0cos(x^2+45)+tan(4x+90) = sin(3x+120) cos(x^2+45)+sin/cos(4x+90) = sin(3x+120) dividing everything by sin. tan(x^2+45) + sec(4x+90) = 3x + 120 i don't remember trig that well, but you can convert it to this i think.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3You can't do that... Like you can't divide by the trig part The trig part is a function not a number or variable on its own

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1Are the angles in radians or degrees?

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1I'll assume degrees for now.

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1Degrees, yeah. ^^

hartnn
 11 months ago
Best ResponseYou've already chosen the best response.045,90,120 suggest they are in degrees... we can convert sin and cos in tan, like cos A = tan (sqrt (1A^2)/A) something like this and then use tan A+tan B formula...... but if thats possible, the algebra is going to be very ugly....

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3but @hartnn tan(90) does not exist you were talking about the sum identity for tan right?

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1@myininaya tan(a+90) = 1/tan(a), since they're perpendicular.

hartnn
 11 months ago
Best ResponseYou've already chosen the best response.0not tan(A+B) tan A +tan B , where B = 4x+90 and yeah, tan (A+90) =  cot 90 so maybe convert cos into cot and use cotAcotB formula... i don't think that will be of any use though....

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1dw:1388481204906:dw

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3I don't like the x squared part much.

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1Series solution is what I'd prefer to us,e but not without an attempt with standard algera.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3or maybe the whole problem i don't see how to do it with algebra/trig He said it was for high school though

hartnn
 11 months ago
Best ResponseYou've already chosen the best response.0even wolf doesn't give integral or rational solutions...

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1Yes, I'm a junior in high school, but the book said High School. It extends way past what I expect to learn in High School, though. I think they may have the age range a bit messed up.

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1No simple way to solve at that level.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3@primeralph if you want, can you show me your series thing you were talking about? You know if you want to.

Confusionist
 11 months ago
Best ResponseYou've already chosen the best response.1I might just go and ask one of the professors at the college I intern at. Thanks for your help, guys. :)

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1First I'd have to convert all to radians.

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1Then find a way to represent the equation as a DE, or simply use the Taylor power series.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3what is equivalent to a (1 radian) squared? That bugs me. The little square there.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3What I'm saying is I'm not used to looking at angles being squared

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1dw:1388481895287:dw

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1@myininaya Yeah I understand, but you'd have to extend your thinking beyond expecting trig to only apply to angles.

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1It will be extensive, but in the end, there might be real solutions.

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3x^2 and 45 will have different units

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3we have x^2=a^2 (degs)^2 and 45 is just in degs not degs^2

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1The x^2 term will be set to have some correction factor. After taking a look at it, I think it's solvable algebraically. It's just long.

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1And with a lot of restrictions to be imposed.

hartnn
 11 months ago
Best ResponseYou've already chosen the best response.0those ugly solutions http://www.wolframalpha.com/input/?i=cos%28x%5E2%2B45%29%2Btan%284x%2B90%29+%3D+sin%283x%2B120%29&dataset=

primeralph
 11 months ago
Best ResponseYou've already chosen the best response.1Don't think you used radians. Wolfram is radians by default.

hartnn
 11 months ago
Best ResponseYou've already chosen the best response.0doesn't make much difference http://www.wolframalpha.com/input/?i=cos%28x%5E2%2Bpi%2F4%29%2Btan%284x%2Bpi%2F2%29+%3D+sin%283x%2B2pi%2F3%29

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3wolfram doesn't want to solve it this is the way input it cos((x deg)^2+45 deg)+tan(4x deg+90 deg)=sin(3x deg+120 deg) http://www.wolframalpha.com/input/?i=cos%28%28x+deg%29%5E2%2B45+deg%29%2Btan%284x+deg%2B90+deg%29%3Dsin%283x+deg%2B120+deg%29

myininaya
 11 months ago
Best ResponseYou've already chosen the best response.3Maybe it doesn't like the unlike units being added either idk
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