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

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

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

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

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

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
that confused me waay more ^^
 11 months 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. \[\frac{a}{b}\]
 11 months ago

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

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

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

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

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

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

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

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

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

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
brb yall meh baby is hungry
 11 months 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 \[ \sin(x)=\sin(x) \]
 11 months 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)
 11 months 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.
 11 months ago

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

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

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

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

highschoolmom2010 Group TitleBest ResponseYou've already chosen the best response.0
ty
 11 months ago

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

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

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