Tìm x thuộc Z
a) (x^2-1).(x^2-25) <0
b) (x^2-4).(x^2-50) <0
bài 1: tìm x thuộc Z
a) 10-x-5=(-5)-7-11
b) (x-3)-(x+17-24)-(25-x)=24-(-30)
c) (7-9x)-(2x-4)=-(5.x+35)-(-27)-(+25)
a: =>5-x=-23
=>x=5+23=28
b: =>x-3-x+7-25+x=54
=>x-21=54
=>x=75
c: =>7-9x-2x+4=-5x-35+27-25=-5x-37
=>-11x+3=-5x-37
=>-6x=-40
=>x=20/3
a) \(10-x-5=\left(-5\right)-7-11\)
\(\Rightarrow5-x=-23\)
\(\Rightarrow x=5+23\)
\(\Rightarrow x=28\)
b) \(\left(x-3\right)-\left(x+17-24\right)-\left(25-x\right)=24-\left(-30\right)\)
\(\Rightarrow x-3-x-17+24-25+x=54\)
\(\Rightarrow x-21=54\)
\(\Rightarrow x=54+21\)
\(\Rightarrow x=75\)
c) \(\left(7-9x\right)-\left(2x-4\right)=-\left(5x+35\right)-\left(-27\right)-25\)
\(\Rightarrow7-9x-2x+4=-5x-35+27-25\)
\(\Rightarrow11-11x=-5x-33\)
\(\Rightarrow-11x+5x=-33-11\)
\(\Rightarrow-6x=-22\)
\(\Rightarrow x=\dfrac{22}{6}=\dfrac{11}{3}\)
a.
10-x-5 = (-5) - 7 -11
=>5-x = 0
=>x=5
b
(x-3) - (x+17-24) - (25-x) = 24 - (-30)
=>x - 3 - x - 17 + 24 - 25 - x = 24 + 30
=>-x - 21 = 54
=>-x = 75
=>x = -75
c
(7 - 9x) - (2x - 4) = - (5x + 35) - (-27) - 25
=>7-9x - 2x + 4 = -5x - 35 + 27 - 35
=>11 - 11x + 5x = -43
=>16x = 11 + 43
=>16x = 54
=>x=4
Tìm x thuộc z
a (x+1)(x+3)
b (x-2)(x-1)(x+3)
Tìm x thuộc z
a,(x-3)(x-1)<0 b,(x-1)(x+4)>0
c,(x+1)(x+3) d,(x-2)(x-1)(x+3)
\(\Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x-3>0\\x-1< 0\end{matrix}\right.\\\left\{{}\begin{matrix}x-3< 0\\x-1>0\end{matrix}\right.\end{matrix}\right.\Leftrightarrow1< x< 3\)
Tìm x,y thuộc Z
a) x^2 +3.x.y+3.y^2=3.y
b) x^2 -2.x.y -5.y^2=y+1
Tìm x,y thuộc Z
a)49-y^2=6(x-2021)^2
b)x^2 + xy + y^2=2x+y
c)x^2 + xy + y^2=x+y
d)x^2 + 3xy + 3y^2 =3y
e)x^2 - 2xy - 5y^2=y+1
Tìm x,y thuộc Z
a)49-y^2=6(x-2021)^2
b)x^2 + xy + y^2=2x+y
c)x^2 + xy + y^2=x+y
d)x^2 + 3xy + 3y^2 =3y
e)x^2 - 2xy - 5y^2=y+1
Tìm x,y thuộc Z
a)49-y^2=6(x-2021)^2
b)x^2 + xy + y^2=2x+y
c)x^2 + xy + y^2=x+y
d)x^2 + 3xy + 3y^2 =3y
e)x^2 - 2xy - 5y^2=y+1
Tìm x,y thuộc Z
a)49-y^2=6(x-2021)^2
b)x^2 + xy + y^2=2x+y
c)x^2 + xy + y^2=x+y
d)x^2 + 3xy + 3y^2 =3y
e)x^2 - 2xy - 5y^2=y+1
Tìm x,y thuộc Z
a)49-y^2=6(x-2021)^2
b)x^2 + xy + y^2=2x+y
c)x^2 + xy + y^2=x+y
d)x^2 + 3xy + 3y^2 =3y
e)x^2 - 2xy - 5y^2=y+1
Tìm x,y thuộc Z
a)49-y^2=6(x-2021)^2
b)x^2 + xy + y^2=2x+y
c)x^2 + xy + y^2=x+y
d)x^2 + 3xy + 3y^2 =3y
e)x^2 - 2xy - 5y^2=y+1