TRIG Brain Freeze This Morning:
I need TAN(A/2) reduced to some TRIG functions of "A"
(Undo the half angle :-) ...Jim Thompson
-- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at
Impossible, you live in Phoenix.
Kevin Aylward B.Sc.
Super! Thanks! ...Jim Thompson
On 27/06/2014 18:51, Jim Thompson wrote:> TRIG Brain Freeze This Morning: > > I need TAN(A/2) reduced to some TRIG functions of "A" > > (Undo the half angle :-) > > ...Jim Thompson
Let t = tan(A/2) T = tan(A)
T = 2t/(1-t^2)
T.t^2 + 2t - T = 0
t = (-2 +/- sqrt(4+4T^2))/2T
t = (-1 +/- sqrt(1+T^2))/T
sanity check tan(pi/3) = sqrt(3)
t = ( -1 +/- sqrt(1+3))/sqrt(3)
t = (-1+/-2)/sqrt(3) = +/- 1/sqrt(3)
subject to typos on a friday night...
wolframalpha.com is good for this sort of question.
Dan
Have something to add? Share your thoughts — no account required.
Ask the community — no account required