\(N=\frac{1}{2x-x^2-4}\)ĐKXĐ : \(x\in R\)
\(N=\frac{1}{-\left(x^2-2x+4\right)}\)
\(N=\frac{1}{-\left(x^2-2x+1+3\right)}\)
\(N=\frac{1}{-\left[\left(x-1\right)^2+3\right]}\)
\(N=\frac{1}{-3-\left(x-1\right)^2}\ge\frac{-1}{3}\forall x\)
Dấu "=" xảy ra \(\Leftrightarrow x-1=0\Leftrightarrow x=1\)( thỏa mãn ĐKXĐ )
Vậy....
Tim GTNN cua bieu thuc
\(M=\frac{x^4+x^2+5}{x^4+2x^2+1}\)
cho x>=2.Tim gtnn cua P=\(2x+\frac{3}{x}+\frac{4}{x^2}\)
1 >Tim GTNN cua :
A = \(\frac{2x^2-16x+43}{x^2-8x+22}\)
cho x,y thuoc R khac 0 thoa man 2x^2 + y^2/4 +1/x^2 = 4. tim gtnn gtln cua A= 2008+xy
Tim gtnn cua 2x/(x-1)^2 khi x>1
Tim gtnn cua bieu thuc A=(2x^2+4x-1)/(x^2+1)
Tim gtnn cua da thuc
Cau 1 M bằng x mũ 2 trừ 8x cộng 5
Cau 2 F bang 2x mũ 2 cộng 6x trừ 4
Tim gtln cua da thúc
Cau 1 7 - x - x mũ 2
Cau 2 ( 1- 2x ) nhân (x-3)
tim GTNN cua
a) A=x2 +3x 5/ x2+2x +1(x khac -1)
b) B = x4+x2+5/ x4+2x2+1
voi x > 1/2
tim gtnn cua D=x/3 + 5/2x-1
