A community for students.
Here's the question you clicked on:
 0 viewing
tanjung
 2 years ago
Help...
Prove that sin36 degrees = sqrt[10  2*sqrt(5)]/4
tanjung
 2 years ago
Help... Prove that sin36 degrees = sqrt[10  2*sqrt(5)]/4

This Question is Closed

tanjung
 2 years ago
Best ResponseYou've already chosen the best response.0next, what's formula using i do

micahwood50
 2 years ago
Best ResponseYou've already chosen the best response.0Seems like it won't help. Try this, using the formula sin (a + b) = cosa sinb + cosb sin a sin36º = 2 sin18º cos18º = 2 cos72º sin72º

tanjung
 2 years ago
Best ResponseYou've already chosen the best response.0ok, i know that formula.. but i think we get the new problem... because sin/cos 18 or sin/cos 72 not eassy to get.. it's very difficul, right ?

micahwood50
 2 years ago
Best ResponseYou've already chosen the best response.0It seems so. Bump your question to get more helps. Maybe someone can help you with this.

tanjung
 2 years ago
Best ResponseYou've already chosen the best response.0@cwrw238 , @experimentX , @estudier , @Hero , @Zarkon , @sauravshakya , @all... help me please, how to get it

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.1dw:1350231015827:dwdw:1350231152168:dw Use quadratic formula dw:1350231253477:dw dw:1350231349862:dw

experimentX
 2 years ago
Best ResponseYou've already chosen the best response.1@ajprincess try thisdw:1350231460480:dw

tanjung
 2 years ago
Best ResponseYou've already chosen the best response.0ok, i get dw:1350231717622:dw

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.1dw:1350231971343:dwdw:1350232035700:dw

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.1@experimentX I tried bt it is a bit complex. cos sin3x=sin108.

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.1Getting it @tanjung?

experimentX
 2 years ago
Best ResponseYou've already chosen the best response.1this should be simpler ... sin(3x) = sin(2x)

tanjung
 2 years ago
Best ResponseYou've already chosen the best response.0not yet, what should i do after that

experimentX
 2 years ago
Best ResponseYou've already chosen the best response.1since this is just double angle and triple angle ... change everything back to sin ... and remove all roots and try to factorize it.

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.1dw:1350232254804:dw

tanjung
 2 years ago
Best ResponseYou've already chosen the best response.0so, just take positive sign in sqrt ?

tanjung
 2 years ago
Best ResponseYou've already chosen the best response.0i know that + it means there are two number here. what about u for it

mukushla
 2 years ago
Best ResponseYou've already chosen the best response.0with positive sign u have sin 36>1 thats impossible

ajprincess
 2 years ago
Best ResponseYou've already chosen the best response.1dw:1350233305717:dw

tanjung
 2 years ago
Best ResponseYou've already chosen the best response.0oh yea, i understand now... thank u very much for ur help , @ajprincess and @mukushla
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.