Răspuns:
a)
[tex]( - \sqrt{6} ) \div \sqrt{2} + ( - 4 \sqrt{15} ) \div ( - \sqrt{5} ) = ( - \sqrt{3} ) + 4 \sqrt{3} = 3 \sqrt{3} [/tex]
b)
[tex]7 \sqrt{10} \div ( - 7\sqrt{5} ) + 4 \sqrt{14} \div ( - 2 \sqrt{7} ) = - \sqrt{2} - 2 \sqrt{2} = - 3 \sqrt{2} [/tex]
c)
[tex]( - 4 \sqrt{15} ) \div 2 \sqrt{3} - \sqrt{35} \div \sqrt{7} = - 2 \sqrt{5} - \sqrt{5} = - 3 \sqrt{5} [/tex]