Hasil dari 3 akar2+3akar8-akar72adalah...

[tex]3 \sqrt{2} + 3 \sqrt{8} - \sqrt{72} = \\ 3 \sqrt{2} + 6 \sqrt{2} - \sqrt{72} = \\ 3 \sqrt{2} + 6 \sqrt{2} - 6 \sqrt{2} = \\ 3\sqrt{2} [/tex]

[tex]3 \sqrt{2} + 3 \sqrt{8} - \sqrt{72} \\ \sqrt{9 \times 2} + \sqrt{9 \times 8} - \sqrt{72} \\ \sqrt{18} + \sqrt{72} - \sqrt{72} \\ \sqrt{9 \times 2} + \sqrt{36 \times 2} - \sqrt{36 \times 2} \\ 3 \sqrt{2} + 6 \sqrt{2} - 6 \sqrt{2} \\ 3 \sqrt{2} [/tex]