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October, 2024

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Math genious wanted

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golf
Posts: 1418 - Karma: 14
if sinA= 4/5 and angle A is in the 1st quadrant find the value of sin2A



the expression sin2A/2cos(squared)A equals?


I have lots more too ne help would b great
May 3 2007 8:33PM
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*rkp*
Posts: 8198 - Karma: 257
maybe you want one for english as well..
May 3 2007 8:33PM
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golf
Posts: 1418 - Karma: 14
yea b/c using proper english on a forum of a bunch of teenagers really impresses ne1
May 3 2007 8:34PM
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marsland
Posts: 3150 - Karma: 421
you have to use an identity for sin2A, i really dont feel like looking for it but i think theres a few of them
May 3 2007 8:36PM
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mistaskia
Posts: 1252 - Karma: 32
yeah i might have it in my bag if u dont no what the identity is.
May 3 2007 8:39PM
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marsland
Posts: 3150 - Karma: 421
hat doesnt look right, .8^2 is .64, i dont know where you got .96
May 3 2007 8:58PM
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duhamelski
Posts: 3842 - Karma: 192
there are a few ways to do this. the easiest way is to go to ur calculator, plug in sin^-1(4/5) and take the result and multiply it by two and then take the sign of that reslut. so its sin(2sin^-1(4/5))
May 3 2007 8:59PM
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chapz
Posts: 10182 - Karma: 66
is that 4 or 536? cause im on 436 and we didnt do sin 2a?
May 3 2007 8:59PM
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marsland
Posts: 3150 - Karma: 421
well i dont know im just real confused right now, in less than a month i forgot how to solve identities, and now i cant do this
May 3 2007 9:03PM
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DDrem.
Posts: 3552 - Karma: 24
ijust had a test on this today. think i did pretty well. dont feel like anymore work
use your trig properties/identities and trig values
May 3 2007 9:04PM
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andy_boy
Posts: 4434 - Karma: 107
I'm pretty sure you're right. I didn't check the numbers but you definitely have the right method.
May 3 2007 9:08PM
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golf
Posts: 1418 - Karma: 14
id ont need your help ne more im going to just copy off someone at school or have them do it for me. I have like 16 problems left
May 3 2007 9:14PM
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SlickRick.
Posts: 4329 - Karma: 300
pwn3d
May 3 2007 9:17PM
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andrewg
Posts: 4746 - Karma: 18
YOU CALLED?
May 3 2007 9:18PM
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golf
Posts: 1418 - Karma: 14
?
May 3 2007 9:27PM
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