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highschoolmom2010
Group Title
Use what you know about trigonometric ratios to show that this equation is
an identity.
 one year ago
 one year ago
highschoolmom2010 Group Title
Use what you know about trigonometric ratios to show that this equation is an identity.
 one year ago
 one year ago

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highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
Sin (x)=cos (x) * tan (x)
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
doesnt make sense to me
 one year ago

katherine.ok Group TitleBest ResponseYou've already chosen the best response.2
you know that tanx = sinx/ cosx/
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
substitute the sin cos tan wid their ratios (opp, adj, hyp)
 one year ago

katherine.ok Group TitleBest ResponseYou've already chosen the best response.2
so sub tanx= sinx/ cosx. this yields left side. left side= right side. QED
 one year ago

katherine.ok Group TitleBest ResponseYou've already chosen the best response.2
tanx= sinx/ cos x because tanx by definition is opp/ adj. sinx= opp/ hyp cos= adj/hyp.
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
that confused me waay more ^^
 one year ago

completeidiot Group TitleBest ResponseYou've already chosen the best response.0
just a note you can use frac{a}{b} in equations to make fractions ex. \[\frac{a}{b}\]
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
work left side separately work right side separately show both are equal
 one year ago

completeidiot Group TitleBest ResponseYou've already chosen the best response.0
\[\tan x = \frac{\sin x}{\cos x}\]
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
left side : sin x = opp/hyp (1)
 one year ago

katherine.ok Group TitleBest ResponseYou've already chosen the best response.2
Okay, i will take it really slowly.
 one year ago

katherine.ok Group TitleBest ResponseYou've already chosen the best response.2
sinx= opp/ hyp= left side.
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
take the right side, substitute opp/adj/hyp, simplify and see if u can get the same as left side
 one year ago

katherine.ok Group TitleBest ResponseYou've already chosen the best response.2
cosx= adj/ hyp; tan x= opp/adj . cosx* tanx= (adj/hyp) (opp/adj); notice adj can be cancelled out> opp/ hyp= sinx. Notice it is same as sinx= left side.
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
\[\frac{ adj }{ hyp }*\frac{ opp }{ adj}\] im really confused :/
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
keep going, one more step. confusion wil go away
 one year ago

katherine.ok Group TitleBest ResponseYou've already chosen the best response.2
top adj can be cancelled out with bottom adj, and you are left with opp/hyp= sinx
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
ok so i was almost there \[\sin (x)=\frac{ opp }{ hyp }\]
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
like that
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
brb yall meh baby is hungry
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.0
the other way is to say \[ \tan(x) = \frac{\sin(x)}{\cos(x)}\] replace tan(x) in \[ \sin(x)= \cos(x) \tan(x) \\ \sin(x)= \cos(x)\frac{\sin(x)}{\cos(x)}\] then notice that cos(x)/cos(x) is 1 you get \[ \sin(x)=\sin(x) \]
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
Right hand side : \(\large \frac{ adj }{ hyp }*\frac{ opp }{ adj} \) \(\large \frac{ \cancel{adj} }{ hyp }*\frac{ opp }{ \cancel{adj}} \) \(\large \frac{ opp }{ hyp } \) (2)
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
from (1) and (2), left hand side = right hand side. so its an identity.
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
oh ok so how do i write it into words
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
you wanto write math into words ? hmm
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
just showing the proof wont do ha ?
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
no i have to write it into words :(
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
okay then describe wat we just did, you may start like below : since left hand side is sinx, and we knw that sinx = opp/hyp, proving right hand side simplifies to opp/hyp is sufficient to prove that given equation is an identity. right hand side we have cosx * tanx. substituting their respective trig ratios, we get adj/hyp * opp/adj....
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
ty
 one year ago

ganeshie8 Group TitleBest ResponseYou've already chosen the best response.0
np, im sure you can conclude :)
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
yea i think i can :D
 one year ago

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
@phi @katherine.ok @ganeshie8 thank you all for for help
 one year ago
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