tu gia thiet => \(4x+4y+4z+4\sqrt{xyz}=16\)
Xet \(\sqrt{x\left(4-y\right)\left(4-z\right)}=\sqrt{x\left(16-4y-4z+yz\right)}\)
= \(\sqrt{x\left(4x+4y+4y+4\sqrt{xyx}-4y-4z+yz\right)}\)
=\(\sqrt{x\left(4x+4\sqrt{xyz}+yz\right)}\)
=\(\sqrt{4x^2+4x\sqrt{xyx}+xyz}=\sqrt{\left(2x+\sqrt{xyz}\right)^2}\)
= \(2x+\sqrt{xyz}\)
tuong tu va suy ra \(\sqrt{x\left(4-y\right)\left(4-z\right)}+\sqrt{y\left(4-z\right)\left(4-x\right)}+\sqrt{z\left(4-x\right)\left(4-y\right)}\)
= \(2\left(x+y+z\right)+3\sqrt{xyz}\)
hinh nhu de bai bn viet thieu \(-\sqrt{xyz}\)
neu dung de thi goi bieu thuc can tinh la A
ta co \(A=2\left(x+y+z\right)+2\sqrt{xyz}=2\left(x+y+z+\sqrt{xyz}\right)=2.4=8\)
Chuc ban hoc tot
jhfghjgjtfyt tjgfyjjtf
sao may ngu the ha di hoi toan tren mang
....???????????????????
M:vvvvvvv
Trl :
Bạn kia làm đúng rồi nhé !
Học tốt nhé bạn @