Answer:
84√3
Step-by-step explanation:
6√21√28
6√7√3√7√4
(6√7√3√7)(2)
(6*7)(√3)(2)
(42)(√3)(2)
[tex]6\sqrt{21} \cdot \sqrt{28}\\\\=6 \left(\sqrt{21 \times 28 \right)\\\\=6\left(\sqrt{588}\right)\\\\=6\left(\sqrt{196 \times 3}\right)\\\\=6\left(14\sqrt 3\right)\\\\=84\sqrt{3}[/tex]
