tim x,y biết
3*x^2*y+6*x^2*y^2+2*y=8
cho x+y=1 tim gtln của a=x^3 + y^3 +x^2+y^2
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 x+y+4=0
Tim max B=2(x^3+y^3)+3(x^2+y^2)+10xy
B1: rut gon bieu thuc
a, (x+y)^2-4(x-y)^2
b, 2(x-y)(x+y)+(x+y)^2+(x-y)^2
B2: tim X
a, (2X-1)^2-4(X+2)^2=9
b, 3(X-1)^2-3X(X-5)=21
B3: Cho bieu thuc
M=(x+3)^3-(x-1)^3+12x(x-1)
a, Rut gon bieu thuc tren
b, Tinh gia tri M tai x=-2/3
c, Tim x de M=16
1.Tim cac cap so nguyen x,y sao cho x+y=2xy
2.Tim GTNN A = x2+3(x-1)2
x+1+x^2+x^3=1987^y voi x,y nguyen tim x,y
bai 1:tim GTNN cua bieu thuc
A=x2+3x+7
B=(x-2)(x-5)(x2-7x-10)
bai 2:tim GTLN cua bieu thuc
A=11-10x-x2
B=[x-4](2-[x-4])
bai 3:tim x,y sao cho
A=2x2+9y2-6xy-6x-12y+2016 co GTNN
B=-x2+2xy-4y2+2x+10y-8 co GTLN
bai 4 :
a)cho x+y=3;x2+y2=5.tinh x3+y3
b)cho x-y=5;x2+y2=15.tinh x3-y3
tim GTNN cua: 3*x^2+y^2-2*x*y-7