anonymous
  • anonymous
Help... Prove that sin36 degrees = sqrt[10 - 2*sqrt(5)]/4
Mathematics
schrodinger
  • schrodinger
See more answers at brainly.com
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.

Get this expert

answer on brainly

SEE EXPERT ANSWER

Get your free account and access expert answers to this
and thousands of other questions

anonymous
  • anonymous
HINT: 180º/5 = 36º
anonymous
  • anonymous
next, what's formula using i do
anonymous
  • anonymous
Seems 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

Looking for something else?

Not the answer you are looking for? Search for more explanations.

More answers

anonymous
  • anonymous
ok, 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 ?
anonymous
  • anonymous
It seems so. Bump your question to get more helps. Maybe someone can help you with this.
anonymous
  • anonymous
ok, thanks...
anonymous
  • anonymous
@cwrw238 , @experimentX , @estudier , @Hero , @Zarkon , @sauravshakya , @all... help me please, how to get it
anonymous
  • anonymous
any idea guys ?
ajprincess
  • ajprincess
|dw:1350231015827:dw||dw:1350231152168:dw| Use quadratic formula |dw:1350231253477:dw| |dw:1350231349862:dw|
experimentX
  • experimentX
@ajprincess try this|dw:1350231460480:dw|
anonymous
  • anonymous
ok, i get |dw:1350231717622:dw|
anonymous
  • anonymous
next ?
anonymous
  • anonymous
upss. sorry, divided 8
ajprincess
  • ajprincess
|dw:1350231971343:dw||dw:1350232035700:dw|
ajprincess
  • ajprincess
@experimentX I tried bt it is a bit complex. cos sin3x=sin108.
ajprincess
  • ajprincess
Getting it @tanjung?
experimentX
  • experimentX
this should be simpler ... sin(3x) = sin(2x)
anonymous
  • anonymous
not yet, what should i do after that
experimentX
  • experimentX
since this is just double angle and triple angle ... change everything back to sin ... and remove all roots and try to factorize it.
ajprincess
  • ajprincess
|dw:1350232254804:dw|
anonymous
  • anonymous
so, just take positive sign in sqrt ?
anonymous
  • anonymous
i know that +- it means there are two number here. what about u for it
anonymous
  • anonymous
with positive sign u have sin 36>1 thats impossible
ajprincess
  • ajprincess
|dw:1350233305717:dw|
anonymous
  • anonymous
oh yea, i understand now... thank u very much for ur help , @ajprincess and @mukushla
ajprincess
  • ajprincess
yw:)

Looking for something else?

Not the answer you are looking for? Search for more explanations.