1) Tim a, b thuoc Q biet: a-b=2(a+b)=a:b
2) Tim x thuoc Q sao cho: (x-1)(x+3)<0
bai 1: Tim x biet
\(\hept{\begin{cases}x-y=\frac{3}{10}\\y\left(x-y\right)=-\frac{3}{50}\end{cases}}\)
bai 2: Tim x, y biet:
x+\(\left(-\frac{31}{12}\right)^2\)=\(\left(\frac{49}{12}\right)^2\)-x=y2
Bai 9: Tim x,y,z biet:
(x-1)2+(x+y)2+(xy-z)2=0
Tim x biet, \(\left(x-2\right)\times\left(x+\frac{2}{3}\right)>0\)
tim x,y,z biet 3y\(^2\)+x\(^2\)+2xy+2x+6y+3=0
a, Cho F(x) = a x+b . Tim a,b biet f(0) = 3 va F(2) =-1
b, Cho F(x) =a x+ b. Tim a,b biet F(1) = -1 va F(-2) = 8
c, Cho F(x) =a x +b .tim a,b biet F(0) = 1 va F(-2) = -9
tim cac gia tri cua x thuoc Q , biet : ( x+1)(x-2)< 0
CHO HAM SO : y=x \(^2\) - 5x +6
a) tim cac gia tri cua x sao cho ve phai cua cong thuc co nghia
b) tinh y ; biet x= -\(\frac{1}{3}\) ; x= 0,5 ; x=0 ; x=1
c) tim x khi biet y = 0
Tim x biet:
(x-3)^2-x/x-3/=0
tim x biet (x^2-1)(x^2-3)(x^2-5)(x^2-7)<=0
