\( \\ Given\quad \sin { \theta } +\sin ^{ 2 }{ \theta } =1\\ find\quad \cos ^{ 12 }{ \theta } +3\cos ^{ 10 }{ \theta } +3\cos ^{ 8 }{ \theta } +\cos ^{ 6 }{ \theta } \quad -1\quad .\)
This was my first question in brilliant ( excluding the question: next number in the sequence 2,4,8.. during account creation).
SincevalueisgivenintermsofsinθIthoughtitmightbebeneficialtoconverttermsofcosθinsinθmoreoveritsapparentthatitcanbedoneeasily.Aftersubstituting(cos2θ=sinθ)Igottheseterms:sin3θ+sin6θ+3sin4θ+3sin5θ−1Whichonrearranginggavethese:⇒sin3θ+sin6θ+3sin3θ(sin2θ+sinθ)−1Ifinallyshottheproblembythis:⇒(sinθ+sin2θ)3−1=0.Iusedtoface(tobehonest,Istillface)difficultywhileattempting′trigo′problems.Theyappeartomesoabsurd.′Whatshouldwedohere?′′Whywouldanyonedothat?′′OK!goodsolutiontherebuthowtoarriveatit?′Thesearethefamilyofquestionscloudingovermymind.So,I(honestlytry)toreasonoutmysteps.IamnotgoodatMathematics.But,IlikeMaths.Hereinbrilliant.org,thereareverytalentedproblemsolvers.IknowitbecauseIhadspentsometimewithmyfriend,inhisprofile,tacklingproblemsandviewingsolutionsandreadingnotes.Thenitalluredmetojoinit.Idon′thavecollectionsofnut−crackingproblemsneithertheabilitytoshootthosetypeofquestionsbutstillifsomearebenefitedinanykindthroughmeIwouldbeglad.
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Wassup Math Philic!
I'm John - and I post the strangest problems around here ;)
I remember the first time I've discovered Brilliant. I Googled "very hard math problems," and clicked a link that led me here - and tell ya what, it's been one hella ride. Throughout the time being, I've discovered a community of intelligent and respectful individuals around the world who not only share math and physics problems and solutions but are willing to address your problems when you need it the most.
Let me introduce you to this site's Bomb Squad:
@Calvin Lin - The White Knight (if he reshares your problem, it's your lucky day!)
@Michael Mendrin - Mr. Mathopedia
@hasan kassim - King Integral
@Mardokay Mosazghi - coolest kid in town.
@jatin yadav - "can't" ain't in his dictionary.
@brian charlesworth - Dr. Philosophy
@Marios Patsios - don't mess with this one...
@David Mattingly - PHYSICS 101
@Arron Kau - Updates!
@Peter Taylor - look at those mountains...
and
@Suyeon Khim - the one who started it all.
ss
There's many more, sorry if I forgot anyone, but trust me, there's WAY more...
Oh yeah...
And hey, don't be shy to try one of my most overrated problems about the Moon and the Universe: How to Climb to the Moon - it's a real teaser!
Oh, and we don't just have problems; we can discuss things all we want. Try out Physics Jokes!
Welcome to the club.
s
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Haha... "Dr. Philosophy" ... You're too funny. :) There were a couple of people on the "Bomb Squad" I wasn't familiar with, so thanks for making the list. I would add @Jon Haussmann as well as "The Annihilator" for the way he mows down countless difficult problems like they're nothin'.
@Math Philic Welcome! Just thought I'd offer a couple of pieces of advice:
If you want more problems, notes, etc., to appear on your feed, just follow those you admire and then their posts and reshares will be placed on your feed.
I notice that all your text is italicized. Most people find this a bit more difficult to read than standard font, so you may want to just use the LaTeX for the "math parts" of your posts. :)
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yes, for the use of latex part one of the moderator @Aditya Raut has helped me. Thanx to u 2 guys.I gonna follow the mentioned guys.. :)
1 more thing.How to mention a name in comment?
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@brian charlesworth
ThanxU missed urself-the cool guy.. thanx mate for this intro..