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Confusionist
 2 years ago
Can someone help me solve this?
cos(x^2+45)+tan(4x+90) = sin(3x+120)
A step by step would be great.
Confusionist
 2 years 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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anonymous
 2 years ago
Best ResponseYou've already chosen the best response.0by solving do you mean proving?

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

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

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

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

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

Confusionist
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.3can you tell me what methods the book has discussed?

Confusionist
 2 years 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.

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

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

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

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

myininaya
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.1Ah, okay. Thanks, anyway. :)

shamil98
 2 years 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
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.1Are the angles in radians or degrees?

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

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

hartnn
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.1dw:1388481204906:dw

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

primeralph
 2 years 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
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.0even wolf doesn't give integral or rational solutions...

Confusionist
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.1No simple way to solve at that level.

myininaya
 2 years 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
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.1First I'd have to convert all to radians.

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

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

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

myininaya
 2 years 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
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.1And with a lot of restrictions to be imposed.

hartnn
 2 years 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
 2 years ago
Best ResponseYou've already chosen the best response.1Don't think you used radians. Wolfram is radians by default.

hartnn
 2 years 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
 2 years 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
 2 years 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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