A community for students. Sign up today!
Here's the question you clicked on:
 0 viewing
 2 years ago
Note to the viewers:This is not a question but short notes on trigonometric identities that may be of some use.
 2 years ago
Note to the viewers:This is not a question but short notes on trigonometric identities that may be of some use.

This Question is Closed

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28dw:1339728896748:dw aopposite badjacent chypotenuse. \[\sin \theta=a/c\] \[\cos \theta=b/c\] \[\tan \theta=a/b\] \[\csc \theta=1/\sin \theta=1/a/c=c/a\] \[\sec \theta=1/\cos \theta=1/b/c=c/b\] \[\cot \theta=1/\tan \theta=1/a/b=b/a\] \[\sin ^{2}\theta+ \cos ^{2}\theta=1\] \[\tan ^{2}\theta+1=\sec ^{2}\theta\] \[1+\cot^{2}\theta=\csc^{2}\theta\] \[tan\theta*\cot\theta=1\] \[sin(A+B)=sinAcosB+sinBcosA\] \[cos(A+B)=cosAcosB+sinAsinB\] \[tan(A+B)=(tanA+tanB)/(1tanA*tanB)\] \[sin(AB)=sinAcosBsinBcosA\] \[cos(AB)=cosAcosBsinAsinB\] \[tan(AB)=(tanAtanB)/(1+tanA*tanB)\]

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28\[sin(A+B)+sin(AB)=2sinAcosB\] \[cos(A+B)+cos(AB)=2cosAcosB\] \[sin(A+B)sin(AB)=2cosAsinB\] \[cos(AB)cos(A+B)=2sinAsinB\] \[sin2\theta=2sin\theta\cos\theta\] \[cos2\theta=cos^2\thetasin^2\theta\] \[cos2\theta=12sin^2\theta\] \[cos2\theta=2cos^2\theta1\] \[tan2\theta=2tan\theta/(1tan^2\theta)\] \[sin3\theta=3sin\theta4sin^3\theta\] \[cos3\theta=4cos^3\theta3cos\theta\] \[sin(\theta)=sin\theta\] \[cos(\theta)=cos\theta\] \[tan(theta)=tan\theta\]

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28\[sin(90\theta)=cos\theta\] \[cos(90\theta)=sin\theta\] \[tan(90\theta)=cot\theta\] \[sin(180\theta)=sin\theta\] \[cos(180\theta)=cos\theta\] \[tan(180\theta)=tan\theta\] \[sin(180+\theta)=sin\theta\] \[cos(180+\theta)=cos\theta\] \[tan180+\theta)=tan\theta\] \[sin(90+\theta)=cos\theta\] \[cos(90+\theta)=sin\theta\] \[tan(90+\theta)=cot\theta\]

maheshmeghwal9
 2 years ago
Best ResponseYou've already chosen the best response.0Nice & thanx @ajprincess :)

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28U r welcome nd thanxx. I thank all who gav me medals for givng them.:)

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28Thanxxx a lot for the comments.:)

experimentX
 2 years ago
Best ResponseYou've already chosen the best response.0seems like you used in few ,,,

lgbasallote
 2 years ago
Best ResponseYou've already chosen the best response.0this is a true tutorial indeed \[\Huge \color{maroon}{\mathtt{\text{<tips hat>}}}\]

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28Thanx a lot @lgbasallote

WONDEMU
 2 years ago
Best ResponseYou've already chosen the best response.0how should I memorize these?

Loujoelou
 2 years ago
Best ResponseYou've already chosen the best response.0I liked it :) Good Job making it :)

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28Thanx a lot @Loujoelou and as for question @wondemu memorise them group by group. For example (1)sin(A+B)=sinAcosB+sinBcosA cos(A+B)=cosAcosB+sinAsinB tan(A+B)=(tanA+tanB)/(1−tanA∗tanB) (2)sin(A−B)=sinAcosB−sinBcosA cos(A−B)=cosAcosB−sinAsinB tan(A−B)=(tanA−tanB)/(1+tanA∗tanB) You'll find them useful when u hav finishd memorising them.

apoorvk
 2 years ago
Best ResponseYou've already chosen the best response.0Simple, clear, lucid, and great! :P

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28Thanx a lot @apoorvk

maheshmeghwal9
 2 years ago
Best ResponseYou've already chosen the best response.0Wow reaching the same target as lgba {30 medals} But hope u would get more than that ^_^

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28Thanx a lot @maheshmeghwal9

mathslover
 2 years ago
Best ResponseYou've already chosen the best response.0good tutorial must appreciate ...

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28Thanx a lot @mathslover.

mathslover
 2 years ago
Best ResponseYou've already chosen the best response.0no thanks @ajprincess actually many of students present here needed this

Calcmathlete
 2 years ago
Best ResponseYou've already chosen the best response.0Good job :) I actually didn't know the negative and triple identities.

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28thanx a lot @calcmathlete

phani09
 2 years ago
Best ResponseYou've already chosen the best response.0that was a good revision.....

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28Thanx a lot @phani09

waterineyes
 2 years ago
Best ResponseYou've already chosen the best response.0@ajprincess , I want to tell you something if you will not feel bad.. May I tell??

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28ya sure. @waterineyes.

waterineyes
 2 years ago
Best ResponseYou've already chosen the best response.0Can you tell me the formulas for \(cos(A + B) \quad and \quad cos(AB)\) ??

waterineyes
 2 years ago
Best ResponseYou've already chosen the best response.0@ajprincess, do you think that you have given the right identities for \(cos(A + B) \quad and \quad cos(A  B)\) ??

Calcmathlete
 2 years ago
Best ResponseYou've already chosen the best response.0@waterineyes is correct. Those two identities are incorrect. \[cos(A + B) = \cos A\cos B  \sin A\sin B\]\[cos(A  B) = \cos A\cos B + \sin A\sin B\]

waterineyes
 2 years ago
Best ResponseYou've already chosen the best response.0See, the difference between \(sin(A \pm B) \quad And \quad cos(A \pm B)\): \[\Large \color{green}{\sin(A \pm B) = sinA.cosB \pm cosA.sinB}\] \[\Large \color{green}{\cos(A \pm B) = cosA.cosB \mp cosA.cosB}\]

waterineyes
 2 years ago
Best ResponseYou've already chosen the best response.0@ajprincess , don't misunderstand me and don't think I always look for mistakes but everywhere you used this identity wrong.. So, I think your mind says it is correct but sorry to say it is incorrect... In sin(A + B) there is respective + in the middle, In sin(A  B) there is respective  in the middle.. But for cos(A + B), there is  in the middle, for cos(A  B), there is + in the middle... Getting it??

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28oh no it's k. Thanx for telling t. i copied it from a note of mine. i must hav written it wrong when I wrote. thanxx a lot for mentioning it. I welcome this sorts of comments. @waterineyes.

waterineyes
 2 years ago
Best ResponseYou've already chosen the best response.026 people gave you medals and I think you deserve more than that.. But how will you let it know to all the 26 people that you have written slight wrong there so that they can know the real formula... Think about it.. @ajprincess ..

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.28it's my mistake nd I am greatly sorry for t. Let me post t again in a new post so that they can get . I am nt sure of any other way other than this.
Ask your own question
Ask a QuestionFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.