Question

1-2cos(3П/2+2П/6)=,,,

Answer 1

1-2cos(3π/2+2π/6)=1-2cos(11π/6)=1-2*√3/2=1-√3

Answer 2

$1-2cos( frac{3 pi }{2} + frac{2 pi }{6} )=1-2cos( frac{9 pi }{6} + frac{ 2pi }{6} )= 1-2cos frac{11 pi }{6} = \ = 1-2cos frac{11 pi }{6} = 1-2cos( pi + frac{5 pi }6} )=1-2cos( pi + pi - frac{ pi }{6} )= \ =1-2cos(- frac{ pi }{6} )=1-2cos frac{ pi }{6} =1-2* frac{ sqrt{3} }{2} =1- sqrt{3}$