Question

Корень из 48*cos^2(11pi/12) -- Корень из 12

Answer 1

4√3*cos165-2√3=4√3cos165-2√3=4√3cos(180-15)-2√3=4√3(-cos15)-2√3=
=-4√3(-√3/2)-2√3=6-2√3
cos15=$sqrt{(1+cos30)/2}$=$sqrt{(1+1/2)/2}$=
=$sqrt{3/4}$=√3/2