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shun
 3 years ago
how can we derive thew formula for half angle for tangent.. pls help..
shun
 3 years ago
how can we derive thew formula for half angle for tangent.. pls help..

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IsTim
 3 years ago
Best ResponseYou've already chosen the best response.0Is this Advanced Functions?

IsTim
 3 years ago
Best ResponseYou've already chosen the best response.0The derivaive of TAN is cosx/sinx I think? Or is that just the reciprocal?

eyust707
 3 years ago
Best ResponseYou've already chosen the best response.1\[\tan \theta = {\sin \theta \over \cos \theta}\]

eyust707
 3 years ago
Best ResponseYou've already chosen the best response.1The derivative of tangent is: \[\frac{ d }{ d \theta } \tan \theta = \sec^2\theta \]

qpHalcy0n
 3 years ago
Best ResponseYou've already chosen the best response.0I think he's looking for a proof of the tangent half angle formula, not an actual derivative.

ash2326
 3 years ago
Best ResponseYou've already chosen the best response.0@shun you want to derive \(\tan \frac {\theta}{2}\)??

ash2326
 3 years ago
Best ResponseYou've already chosen the best response.0We know that \[\tan (A+B)=\frac{\tan A+\tan B}{1\tan A\times \tan B}\] Put \[A=B=\frac {\theta}{2}\] \(\large \text{you'd get a relation of}\ \tan \theta \ \text{in terms of} \tan \frac{\theta}2\)

qpHalcy0n
 3 years ago
Best ResponseYou've already chosen the best response.0Here, to prove it, use the half angle formulae for sine and cosine. \[\sin(x/2) = \pm \sqrt{ (1cosx / 2}\] \[\cos(x/2) = \pm \sqrt{ (1+cosx / 2) }\]

shun
 3 years ago
Best ResponseYou've already chosen the best response.0@ash yes,, actually,, it is,

satellite73
 3 years ago
Best ResponseYou've already chosen the best response.0\[\frac{\text{half angle formula for sine}}{\text{half angle formula for cosine}}\]

shun
 3 years ago
Best ResponseYou've already chosen the best response.0@qp tnx.. i get it.. tank you.. but that it is the formulaim asking for the derivation.. ..

qpHalcy0n
 3 years ago
Best ResponseYou've already chosen the best response.0The derivation is based on those formulae. The half angle tangent is half angle sine / half angle cosine. You can prove half angle sine and cosine as well, if needs be.

shun
 3 years ago
Best ResponseYou've already chosen the best response.0@sat.. yes that the beginning.. did you know some restrictions?

shun
 3 years ago
Best ResponseYou've already chosen the best response.0@qp ok ok.. i get it.. tnx,,,
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