Sa se calculeze a si b: a)a=6√3+√108-4√75+2√147

b=8√3+33√12-5√27

b)a=3√2+11√7-2√112-√200

b=3√28+2√63-√252-√175

c)a=22√7-√648-√567+2√162

b=3√567-√800+2√200+10√175