Show that 12 cos 30° - 2 tan 60° can be written in the form√ k where k is an integer

Firstly work out (using the sin cos tan triangle and soh cah toa) what cos 30° and tan 60° are equal to so tan 60° = √3 and cos 30° = √3 / 2 then substitute these values into the euqation giving 12 x √3 / 2 - 2 √3 which can be simplified to 6 √3 - 2 √3 (because the 12 is divisible by 2) this can be simplified further to 4√3 (because the √3 is consistent in each number you can simply do 6-2 = 4)