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Advanced Math/Trig Identities
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Question
ok, i have tried everything to get this proof to work, and i dont think it does, here is the question
COS 2(t)= [2-SEC^2(t)]/SEC^2(t)
if by this you mean
cos(2t) = (2 - sec(t)^2)/(sec(t)^2))
(2 - (1/cos(t))^2)/(1/cos(t)^2)
((2cos(t)^2 - 1)/cos(t)^2)/(1/cos(t)^2)
(2cos(t)^2 - 1)/cos(t)^2) * cos(t)^2
2cos(t)^2 - 1
cos(2t) = 2cos(t)^2 - 1
so
cos(2t) = (2 - sec(t)^2)/(sec(t)^2))
info found at http://math2.org/math/trig/identities.htm
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| Rating(1-10) | Knowledgeability = 10 | Clarity of Response = 10 | Politeness = 10 |
| Comment | thank you! i kinda headed down that road, but forgot that you could change it like that. thank you very much | ||
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Advanced Math
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Sherman D.
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