>>604
>2cos^2t=1+(-2+√3)/2=√3/2
>0＜t＜π/3
>cost=cos(π/3-θ)=√(√3/2)>√3/2
ああ間違えた
cost=√√3/2<√3/2
π/6<t<π/3
0<θ<π/6
(1/2)cosθ+(√3/2)sinθ=√√3/2
cosθ+√3sinθ=√√3
cos^2θ+sin^2θ=1
cosθ=(√√3+√(4√3-3))/4
sinθ=(√(3√3)-√(4-√3))/4
y=(√(25√3-24)-√(4√3-3))/3