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 hai so duong xy thoa man \(\frac{4}{x^2}+\frac{5}{y^2}\ge9\) tim gia tri nho nhat cua bieu thuc\(Q=2x^2+\frac{6}{x^2}+3y^2+\frac{8}{y^2}\)
Tim tat cac cac cap so nguyen x,y thoa man a) x^2+5xy+4y^2
b)xy-2x+3y-1
Tim tat cac cac cap so nguyen x,y thoa man a) x^2+5xy+4y^2
b)xy-2x+3y-1
Tim tat cac cac cap so nguyen x,y thoa man a) x^2+5xy+4y^2
b)xy-2x+3y-1
cho cac so thuc x,y thoa man 1/x^2+4+1/y^2+4=2/xy+4.Tinh gia triP=1/x^2y^2+4+4/xy+4
1.gia tri x<0 thoa man (2x-3)2=(x+5)2
2.tap hop cac gia tri cua x thoa man x4-2x3+10x2-20x=0 la S(....)
3.phan tich da thuc xy-12+3x-4 ta duoc (x+a)(y+b) khi do a+b=?
cho x+y=5 tim max A=x^4+y^4-4(x^3+y^3)-20(x^2+y^2)-2x^2y^2+xy
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
