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Jonask
show that
\[\huge\tan 7^{0}30 '=\sqrt{6}+\sqrt{2}-\sqrt{3}-2\]
what is this \['\] notation
the single ' means arc minutes, usually just called minutes, meaning 1/60 of a degree See http://zonalandeducation.com/mmts/trigonometryRealms/degMinSec/degMinSec.htm 30' means 30/60 of a degree or 0.5 degrees 7º 30' = 7.5º
tan(7.5) =tan(15/2) tan(15)=tan(30/2) tan(30)=1/root3
This should help tanx=2tan(x/2) /(1-tan^2(x/2) ) So, |dw:1358674326162:dw|