A community for students.
Here's the question you clicked on:
← 55 members online
 0 viewing
DLS
 4 years ago
cos36?
DLS
 4 years ago
cos36?

This Question is Closed

hartnn
 4 years ago
Best ResponseYou've already chosen the best response.1first can u find sin 18 without calcy ?

hartnn
 4 years ago
Best ResponseYou've already chosen the best response.1let x= 18 5x = 90 3x = 902x now take sin on both sides.

hartnn
 4 years ago
Best ResponseYou've already chosen the best response.1sin 3x = sin(902x) sin 3x = cos 2x

hartnn
 4 years ago
Best ResponseYou've already chosen the best response.1now put the formula fo sin 3x and cos 2x in terms of powers of sin x only.

hartnn
 4 years ago
Best ResponseYou've already chosen the best response.1u get a cubic in sin x. solve it.

DLS
 4 years ago
Best ResponseYou've already chosen the best response.1wait,theres a formula for sin3x? :P

hartnn
 4 years ago
Best ResponseYou've already chosen the best response.1sin 3x = 3sin x  4 sin^3 x

DLS
 4 years ago
Best ResponseYou've already chosen the best response.1okay I guess i can do it now

hartnn
 4 years ago
Best ResponseYou've already chosen the best response.1from sin 18, u get cos 36 from the formula of cos 2x in terms of sin x
Ask your own question
Sign UpFind 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.