Réponse :
en utilisant π/6 calculer tan π/12
or π/12 = π/4 - π/6
on utilise donc tan (a - b) = [tan (a) - tan (b)]/(1+ tan(a)tan(b))
tan(π/4 - π/6) = (tan(π/4) - tan (π/6))/(1+tan(π/4)tan(π/6)
tan(π/4) = sin (π/4)/cos(π/4) = 1
tan (π/6) = √3/3
tan (π/4 - π6) = (1 - √3/3)/(1 + √3/3) = (3-√3)/(3+√3) = (3 -√3)²/6 = 2 - √3
Explications étape par étape
