cho 2 so x va y thoa man 3x+y=1
a) Tim GTNN cua bt M=3x^2+y^2
b) Tim GTLN cua bt N=x*y
Cho x,y la hai so thuc thoa man x+y=2.Tim gtln cua bt M=x2y2(x2+y2) - HELP ME-
cho cac so thu cx,y thoa man 4/x^2+5/y^2 >=9 tim GTNN cua bt
Q=2x^2+6/x^2+3y^2+8/y^2
Áp dụng bđt AM-GM:
\(2x^2+\frac{6}{x^2}+3y^2+\frac{8}{y^2}\)
\(=\left(2x^2+\frac{2}{x^2}\right)+\left(3y^2+\frac{3}{y^2}\right)+\left(\frac{4}{x^2}+\frac{5}{y^2}\right)\)
\(\ge2\sqrt{\frac{4x^2}{x^2}}+2\sqrt{\frac{9y^2}{y^2}}+\left(\frac{4}{x^2}+\frac{5}{y^2}\right)\ge4+6+9=19\)
\("="\Leftrightarrow x=y=\pm1\)
a)Tim cap (x,y) nguyen duong thoa man xy=3(y-x)
b)cho 2 so x,y >0 thoa man x+y = 1
Tim GTNN cua M=(x^2+1/y^2)(y^2+1/x^2)
mình biết làm nhưng dài quá bạn tra trên google là đc
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
cho x,y thoa man 3x+y=1 tim gt nn cua A=3x*x=y*y
cho x;yla 2 sô khac nhau x^2+2y^2+2xy+3x+3y-4=0 tim gtnn va GTLN cua A=x^2+y^2
Tim gtln va nho nhat cua x, y thuc thoa man:
X2 + XY + Y2 - Y = 0
cho cac so thuc x,y thoa man x^2+y^2-xy-9 tim GTNN cua P= x^2+y^2
help meeeeeeee
cho cac so thuc x,y thoa man x^2+y^2-xy-9 tim GTNN cua P= x^2+y^2
help meeeeeeeeeeee