\(=2x-\frac{2.3}{2\sqrt{2}}.\sqrt{2x}+\frac{9}{8}+\frac{23}{8}\)
\(=\left(\sqrt{2x}-\frac{3\sqrt{2}}{2}\right)^2+\frac{23}{8}\ge\frac{23}{8}\)
=> GTNN của BT là 23/8
tim GTNN cua bieu thuc :
\(x^2-4\sqrt{x}-7\)
\(\frac{2017-2015x}{\sqrt{1-x^2}}\)
tim GTNN cua bieu thuc tren
TIm GTNN cua bieu thuc
\(x^2-4x+3\)
Voi x>=-2.Tim GTNN cua bieu thuc N=x^2+2x+1/(x+2)
cho cac so thuc duing x,y thoa man x+y<=3.Tim GTNN cua bieu thuc : P=1/5xy + 5/x+2y+5
Cho bieu thuc: \(p=\left(\frac{1}{\sqrt{x}-\sqrt{x-1}}-\frac{x-3}{\sqrt{x-1}-\sqrt{2}}\right)\left(\frac{2}{\sqrt{2}-\sqrt{x}}-\frac{\sqrt{x}+\sqrt{2}}{\sqrt{2x}-x}\right)\)
a) Tim DKXD cua bieu thuc p
b) Rut gon bieu thuc p
\(\sqrt{x^2+4x+4}+\sqrt{x^2-6x+9}\) tim gia tri nho hat cua bieu thuc
Cho bieu thuc P=\(\frac{a^2+\sqrt{a}}{a-\sqrt{a}+1}-\frac{2a+\sqrt{a}}{\sqrt{a}}+1\)
Rut gon bieu thuc P ( lam rui ) Biet a>1 Hay so sanh P voi tri tuyet doi cua P ( chua lam )Tim GTNN cua P ( chua lam )
Tim GTLN ,GTNN cua bieu thuc :A=\(\frac{x+1}{x^2+x+1}\)
