Question

menos raiz terceira de menos 343

Answer 1

$-\,^{3}\!\!\!\sqrt{-343}\\\\ =-\,^{3}\!\!\!\sqrt{(-1)\cdot 343}\\\\ =-\,^{3}\!\!\!\sqrt{-1}\cdot \,^{3}\!\!\!\sqrt{343}\\\\ =-(-1)\cdot \,^{3}\!\!\!\sqrt{343}\\\\ =1\cdot \,^{3}\!\!\!\sqrt{343}\\\\ =\,^{3}\!\!\!\sqrt{343}\\\\ =\,^{3}\!\!\!\sqrt{7^{3}}\\\\ =7\\\\\\ \therefore~~\boxed{\begin{array}{c}-\,^{3}\!\!\!\sqrt{-343}=7 \end{array}}$