Помогите, пожалуйста

Решите задачу:

$((4 \sqrt{6}+ \sqrt{39})+(2 \sqrt{26}+6)) ((4 \sqrt{6}+ \sqrt{39})-( 2\sqrt{26}+6)) \\ 4 \sqrt{6}+ \sqrt{39}=a \\ 2 \sqrt{26}+6=b \\ (a+b)(a-b)=a^2-b^2 \\ \\ (4 \sqrt{6}+ \sqrt{39})^2 = 96+8 \sqrt{2*3*3*12}+39 = 96+24 \sqrt{24}+39= \\ =135+24 \sqrt{24} \\ \\ (2 \sqrt{26}+6)^2=104+24 \sqrt{26}+36 =140+24 \sqrt{26} \\ \\ a^2-b^2 = 135+24 \sqrt{24} - (140+24 \sqrt{26}) = \\ =135+24 \sqrt{24}-140-24 \sqrt{26}=-5+24 \sqrt{24} -24 \sqrt{26} = \\ =-5+24 \sqrt{2}( \sqrt{12}- \sqrt{13})$