# Trig - tan 15° using composite argument?

posted by Anonymous

tan 15°
tan (45°-30°)
(tan 45° - tan 30°)/1+ tan 45°tan30°
(1-√3/3)/(1+1√3/3)

then i donnt what to do/ chancel out. Can someone finish it if i didn't get it wrong.

1. bobpursley

I would rationalize the denominator

(1-1/3 sqrt3)^2/(1-1/3)=3(1-1/3 sqrt3)^2/2

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