Resposta:
[tex] \sqrt{2} \times \sqrt{9} = \sqrt{2 \times 9} = \sqrt{18} [/tex]
[tex] \sqrt{9} \div \sqrt{3} = \sqrt{9 \div 3} = \sqrt{3} [/tex]
[tex] \sqrt{5} \times \sqrt{12} = \sqrt{5 \times 12} = \sqrt{60} [/tex]
[tex] \sqrt{20} \div \sqrt{4} = \sqrt{20 \div 4 } = \sqrt{5} [/tex]
[tex] \sqrt{6} \times \sqrt{2} = \sqrt{6 \times 2} = \sqrt{12} [/tex]
[tex] \sqrt{15} \div \sqrt{5} = \sqrt{15 \div 5} = \sqrt{3} [/tex]
