[tex]4 \sqrt{84} -10 \sqrt{189} -12 \sqrt{1029} +2 \sqrt{525} =[/tex][tex]4 \sqrt{2 ^{2}*3*7 } -10 \sqrt{3 ^{3}*7 } -12 \sqrt{ 7^{3}*3 } +2 \sqrt{5 ^{2} *3*7} =[/tex][tex]4*2 \sqrt{3*7 } -10*3 \sqrt{3 *7 } -12*7 \sqrt{ 7*3 } +2*5 \sqrt{ 3*7} =[/tex][tex]8 \sqrt{21} -30 \sqrt{21 } -84 \sqrt{ 21 } +10 \sqrt{ 21} =-96 \sqrt{21} =-96*4,58=-439,68[/tex]
