Question

ххееллллппппппппп плиз​

Answer 1

1) $\left(\sqrt[6]{27}+\sqrt[4]{64}\right)\left(\sqrt[6]{27}-\sqrt[4]{64}\right)=\left(\sqrt[6]{3^3}+\sqrt[4]{2^6}\right)\left(\sqrt[6]{3^3}-\sqrt[4]{2^6}\right)=$

$=\sqrt[6]{3^6}-\sqrt[4]{2^{12}}=3-8=-5.$

2) $49+20\sqrt{6}=49+2\sqrt{600}=25+2\sqrt{25}\cdot\sqrt{24}+24=(5+\sqrt{24})^2=(5+2\sqrt{6})^2\Rightarrow$

$\left(\sqrt[6]{49+20\sqrt{6}}+\sqrt[3]{5+2\sqrt{6}}\right)\cdot\sqrt[3]{5-2\sqrt{6}}=2\sqrt[3]{5+2\sqrt{6}}\cdot\sqrt[3]{5-2\sqrt{6}}=$

$=2\sqrt[3]{25-24}=2\sqrt[3]{1}=2\cdot 1=2$