Question

Объясните и помогите решить №400, пожалуйста!

Answer 1

$1)sqrt{7+4sqrt{3}} =sqrt{4+2*2*sqrt{3}+3 }=sqrt{(2+sqrt{3} )^{2} }=|2+sqrt{3}|=2+sqrt{3}$

$2)sqrt{6-2sqrt{5} }= sqrt{5-2sqrt{5}+1 }=sqrt{(sqrt{5}-1)^{2}}=|sqrt{5}-1|=sqrt{5} -1$

$3)sqrt{5+2sqrt{6} }= sqrt{3+2sqrt{6}+2 }=sqrt{(sqrt{3} +sqrt{2})^{2}}=|sqrt{3}+sqrt{2}|=sqrt{3}+sqrt{2}$

$4)sqrt{3-sqrt{8} }=sqrt{3-2sqrt{2} }=sqrt{2-2sqrt{2}+1 }=sqrt{(sqrt{2}-1)^{2}} =|sqrt{2}-1|=sqrt{2}-1$