Ta có bảng xét dấu
x -1 2
x+1 - 0 + I +
x-2 - I + 0 +
(x+1)(x-2) - 0 + 0 +
=> (x+1)(x-2) < 0 khi x<-1 hoặc -1<x<2
Ta có bảng xét dấu
x -1 2
x+1 - 0 + I +
x-2 - I + 0 +
(x+1)(x-2) - 0 + 0 +
=> (x+1)(x-2) < 0 khi x<-1 hoặc -1<x<2
tim cac gia tri cua x thuoc Q , biet : (x-2 ) : (3x+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 gia tri tuyet doi cua x-a=a biet a thuoc Z
Tim tap hop cac gia tri cua x biet:
2016.|x-1|+(x-1)2=2015.|1-x|
tim x biet gia tri tuyet ds cua x\(^2\)+gia tri tuyet ds cua x-1 =x\(^2\)+2
Tim cac gia tri cua X de biet thuc sau nhan gia tri am
a)x^2+5x
b)3x(2x+3)x(4y-3)
c1: Tap hop cac gia tri nguyen cua x thoa man \(\left(x+\frac{5}{4}\right)\left(x-\frac{19}{7}\right)\)<0
c2: Neu x,y la cac so nguyen thoa man 2xy+4y=6 thi y co the nhan nhung gia tri nam trong tap hop nao
c3: tim 3 so x,y,z biet x+y=8,x+z=10,y+z=12
C4: Gia tri cua x thoa man (x+3)^2=25 va x^3>0 la x=
tim cac gia tri x y thoa man
a,(x^2-1)(x^2-16)<0 va x thuoc Z
B,1/x-y/8=1/16 va x y thuoc N
Chof(x)=x^2-1 tim cac gia tri cua x sao cho f(1-x)nhan gia tri am