Question

tính :

A=\(\dfrac{\sqrt{2}+\sqrt{3}+\sqrt{6}+\sqrt{8}+4}{\sqrt{2}+\sqrt{3}+\sqrt{4}}\)

B=\(\sqrt{14+\sqrt{40}+\sqrt{56}+\sqrt{140}}\)

Answer 1

\(A=\dfrac{\sqrt{2}+\sqrt{3}+\sqrt{4}+\sqrt{6}+\sqrt{8}+\sqrt{4}}{\sqrt{2}+\sqrt{3}+\sqrt{4}}\)

\(=\dfrac{\sqrt{2}+\sqrt{3}+\sqrt{4}+\sqrt{2}\left(\sqrt{2}+\sqrt{3}+\sqrt{4}\right)}{\sqrt{2}+\sqrt{3}+\sqrt{4}}\)

\(=1+\sqrt{2}\)

Answer 2

SBT nha

Answer 3

B=\(\sqrt{14+2\sqrt{10}+2\sqrt{14}+2\sqrt{35}}\)

B=\(\sqrt{7+5+2+2\sqrt{2.5}+2\sqrt{2.7}+2\sqrt{7.5}}\)

B=\(\left(\sqrt{\sqrt{7}+\sqrt{5}+\sqrt{2}}\right)^2\)

B=\(\sqrt{7}+\sqrt{5}+\sqrt{2}\)