Question

simplify 4√81 -8 3√343+15 5√32 +√225

Answer 1

$\sqrt[4]{81} = {3}^{4} = 81 \\ \sqrt[3]{7} = {7}^{3} = 343 \\ \sqrt[5]{2} = {2}^{5} = 32 \\ \sqrt{225} = {15}^{2} = 225 \\ 3 - 8 \times 7 + 15 \times 2 + 15 = - 8$

Answer 2

Given:

$\sqrt[4]{81}-8\sqrt[3]{343}+15\sqrt[5]{32}+\sqrt[2]{225}$

$=\sqrt[4]{3^4}-8\sqrt[3]{7^3}+15\sqrt[5]{2^5}+\sqrt[2]{15^2}$

$=3-8\times7+15\times2+15$

$=3-56+30+15$

$=-8$

Therefore:

$\sqrt[4]{81}-8\sqrt[3]{343}+15\sqrt[5]{32}+\sqrt[2]{225}=-8$.