BT:Tìm x,y thoả mãn :
a) | x - 2017 | + | y- 2018 | < 0
b) 3.| x - y |5 + 10.| y + \(\dfrac{2}{3}\)|7 \(\le\) 0
c) \(\dfrac{1}{2}\). ( \(\dfrac{3}{4}x-\dfrac{1}{2}\))2018 + \(\dfrac{2017}{2018}\).|\(\dfrac{4}{5}y+\dfrac{6}{25}\)| \(\le\)0
d) 2017.|2x - y|2018 + 2018.|y - 4 | \(\le\) 0
... Helpppp Meeee vs các bn yêu dấu !!!!
Tìm y biết:
a) 2y . (y - \(\dfrac{1}{7}\)) = 0
b) \(-\dfrac{2}{5}+\dfrac{2}{3}y+\dfrac{1}{6}y=\dfrac{-4}{15}\)
Tìm các số x thỏa mãn:
a) \(x.\left(x-\dfrac{4}{7}\right)>0\)
b)\(\left(x-\dfrac{2}{5}x^2\right)< 0\)
c)\(\left(x-\dfrac{2}{5}\right).\left(x+\dfrac{3}{7}\right)>0\)
d)\(\left(x-\dfrac{2}{5}\right).\left(x+\dfrac{3}{7}\right).\left(x+\dfrac{3}{4}\right)>0\)
(* dấu . là dấu nhân nha bạn ^-^)
I : tìm x
a) (x-1)(x-5)>0
b) (x-1)(x-5)<0
c) \(\dfrac{3}{4}-\dfrac{1}{4}\left|x-\dfrac{1}{7}\right|=\dfrac{1}{4}\)
d) \(\left(x-\dfrac{1}{2}\right)^2=\dfrac{1}{16}\)
e) 8 (x+1) -2(2x+5)=0
g) ( 6x-1)-(x+8)=0
h)\(\left|7x-\dfrac{1}{4}\right|=1\)
q) -2x-3=-x+7
các bạn giúp mình với xin đó đấy
1/ Cho \(a,d>0\) và \(\dfrac{a}{b}< \dfrac{c}{d}\). CMR: \(\dfrac{a}{b}< \dfrac{a+c}{b+d}< \dfrac{c}{d}\)
2/ Cho a,b \(\in\) Z. So sánh \(\dfrac{a}{b}\)và \(\dfrac{a+2018}{b+2018}\)
3/ Tìm x,y biết \(\dfrac{x}{6}-\dfrac{1}{y}=\dfrac{1}{2}\)
a: (x-1) ( x+5) > 0
b: (x-1) ( x+5) < 0
c) \(\left(x-\dfrac{1}{2}\right)^2=\dfrac{1}{16}\)
d)\(\dfrac{3}{4}-\dfrac{1}{4}\left|x-\dfrac{1}{7}\right|=\dfrac{1}{4}\)
e) 8 ( x+1) - 2 ( 2x + 5 ) = 0
g) ( 6x-1) - ( x + 8 ) =0
h) \(\left|7x-\dfrac{1}{4}\right|=1\)
x) -2x-3=-x+7
Cho A= 1 + \(\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}+...+\dfrac{1}{4034}\); B = 1 + \(\dfrac{1}{3}+\dfrac{1}{5}+\dfrac{1}{7}+...+\dfrac{1}{4033}\)
So sánh \(\dfrac{A}{B}\)với 1\(\dfrac{2017}{2018}\)
Tìm x,y,z biết :
1) \(x:y:z=3:5:\left(-2\right)\) và \(5x-y+3z=-16\)
2) \(\dfrac{x}{2}=\dfrac{y}{-3};\dfrac{z}{3}=\dfrac{y}{4}\) và \(x+y+z=5,2\)
3) \(2x=3y;7z=5y\) và \(3x-7y+5z=30\)
4) \(3x=4y=5z\) và \(x-\left(y+z\right)=-21\)
5) \(\dfrac{x-1}{2}=\dfrac{y-2}{3}=\dfrac{z-3}{4}\) và \(2x+3y-z=50\)
1) \(\dfrac{x}{5}=\dfrac{y}{3}\) và x-y=20
2) \(\dfrac{x}{y}=\dfrac{3}{4}\) và x+y=90
3) \(\dfrac{x}{5}=\dfrac{y}{2}=\dfrac{z}{3}\) và 2x+3y+4z=54
tìm x:
a,(x - 2)3= -27 b,(2x + 1)4 =81 c,2x + 2x + 3 = 144 d,(5x - 2)10 = (5x - 2)100
e,(\(\dfrac{2x-3}{4}\) )2016 + (\(\dfrac{3y+4}{5}\))2018 = 0