ta có :
x2 = y2 (x + y4 + 2y2 )
<=> x2 -xy2 -y6 -2y4 =0
△= b2 -4ac
= y4 -4(-y6 -2y4 )
=9y4 +4y6 >=0 (mũ chẵn luôn luôn >=0)
=> pt có 2 nghiệm
x1 = (-b +√△)/2a = (y4 +√9y4 +4y6)/2
x2 = (-b - √△)/2a = (y4 - √9y4 +4y6)/2
dùng máy tính lập bảng để tìm nghiệm ta có : x= 12, y=2
tim tat ca cac so tu nhien x y thoa man x^2=y^2(x+y^4+2y^2)
cho hai so thuc x,y thoa man x^2+y^2=1. tim gia tri nho nhat cua p=x^6+y^6
cho 2 so x, y thoa man: x2+x2y2-2y=0 va x3+ 2y2-4y+3=0
tinh gia tri cua bieu thuc Q=x2+y2
Tim ba so duong thoa man : \(2016\left(x-y\sqrt{2001}\right)=2015\left(y-\sqrt{2001}\right)\) va \(x^2+y^2+z^2\) la so nguyen to
tim cac cap so nguyen x; y biet
x^2+2y^2+3xy+3x+5y=15
tim cac so nguyen x va y sao cho (x^2-x+1)(y^2+xy)=3x-1
tinh gt cac bieu thuc sau :
a, A=(x^2y+y^3) (x^2+y^2)-y(x^4+y^4)
b,B=(2x-y) (2x+y)-100
voi x=-25 , y=10
Cho x,y,z thoa man \(\frac{x}{y+z}+\frac{y}{z+x}+\frac{z}{x+y}=1\). Tinh M = \(\frac{x^2}{y+z}+\frac{y^2}{z+x}+\frac{z^2}{x+y}\)
cho 3 so thoa man \(\dfrac{1}{x}+\dfrac{1}{y}+\dfrac{1}{z}=0\)
CM: \(\dfrac{1}{x^2+2yz}+\dfrac{1}{y^2+2zx}+\dfrac{1}{z^2+2xy}=0\)
