a. \(\left|x+2\right|>7\Leftrightarrow\left[{}\begin{matrix}x+2>7\\x+2< -7\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x>5\\x< -9\end{matrix}\right.\)
Vậy...
b. \(\left|x-1\right|< 3\)
Tìm số hữu tỉ x,y:
a,\(\left|-x+2\right|-\left|x+7\right|=0\)
b,\(\left|2x-1\right|+\left|2+y\right|\ge0\)
HeLp Me
Tìm x,biết
a, \(\frac{3}{\left(x+2\right)\left(x+5\right)}+\frac{5}{\left(x+5\right)\left(x+10\right)}+\frac{7}{\left(x+10\right)\left(x+17\right)}=\frac{x}{\left(x+2\right)\left(x+17\right)}\)
Với x ∉ -2,-5,-10,-17
b,\(\frac{2}{\left(x-1\right)\left(x-3\right)}+\frac{5}{\left(x-3\right)\left(x-8\right)}+\frac{12}{\left(x-8\right)\left(x-20\right)}-\frac{1}{x-20}=\frac{-3}{4}\)
Với x∉1,3,8,20
c,\(\frac{x-1}{2009}+\frac{x-2}{2008}=\frac{x-3}{2007}+\frac{x-4}{2006}\)
tìm x, biết
a) \(\left|x+2\right|+\left|x-3\right|=7\)
b) \(\left|x+2\right|-6x=1\)
c) \(\left|2x+1\right|+\left|x+8\right|=4x\)
d) \(x+\left|x+2017\right|=-2017\)
Tìm x, biết:
a) \(\left(x-\frac{-7}{8}\right)+2,3=3,24\) ; b) \(x.\left(4,6+\frac{3}{5}\right)=7,2-8,15\) ; c) |2x-3|+3=16 ; d) \(42+\frac{3}{7}.\left|3x-1\right|=12\)
e) \(\left(x-\frac{1}{2}\right).\left(1+5x\right)=0\) ; f) |2x-1|=|x+2| ; g) \(2.3^x.3^2=18\left(x\in N\right)\) ; h) \(\frac{x+2}{5}=\frac{2-3x}{3}\)
1)Tính giá trị biểu thức:
\(\dfrac{\left(13\dfrac{1}{4}-2\dfrac{5}{27}-10\dfrac{5}{6}\right).230\dfrac{1}{25}+46\dfrac{3}{4}}{\left(1\dfrac{3}{7}+\dfrac{10}{3}\right):\left(12\dfrac{1}{3}-14\dfrac{2}{7}\right)}\)
2)Tìm x biết:
a) \(42+\dfrac{3}{7}.\left|3x-1\right|=12\)
b) \(\left|2x-1\right|=\left|x+2\right|\)
c) \(2.3^x.3^2=18\) với \(x\in N\)
a)\(\frac{-3}{2}-2x+\frac{3}{4}=-2\)
b)\(\left(\frac{-2}{3}x-\frac{3}{5}\right)\left(\frac{3}{-2}-\frac{10}{3}\right)=\frac{2}{5}\)
c)\(\frac{x}{2}-\left(\frac{3x}{5}-\frac{13}{5}\right)=-\left(\frac{7}{5}+\frac{7}{10}.x\right)\)
d)\(\frac{2x-3}{3}+\frac{-3}{2}=\frac{5-3x}{6}-\frac{1}{3}\)
e)\(\frac{2}{3x}-\frac{3}{12}=\frac{4}{5}-\left(\frac{7}{x}2\right)\)
k)\(\frac{13}{x-1}+\frac{5}{2x-2}-\frac{6}{3x-3}\)
m)\(\left(\frac{3}{2}-\frac{2}{-5}\right):x-\frac{1}{2}=\frac{3}{2}\)
n)\(\left(\frac{3}{2}-\frac{5}{11}-\frac{3}{13}\right)\left(2x-2\right)=\left(\frac{-3}{4}+\frac{5}{22}+\frac{3}{26}\right)\)
Giải giúp mk
mk đang cần ghấp trong hôm nay
cám ơn mọi người
tìm x
a) \(\left|\dfrac{1}{3}x\right|\cdot\left|-2.7\right|=\left|-3\right|\)
b) \(2\left|2x-1\right|+\left|-7\right|=19\)
c) \(\left|x\right|>2\)
d)\(\left|x+a\right|< 2\)
f) \(\left|3x-2\right|\ge4\)
1 tính
a, \(-\dfrac{2}{3}-\left(\dfrac{-2}{5}\right)-\dfrac{7}{10}\)
b, \(\dfrac{-5}{9}.\left(\dfrac{3}{10}-\dfrac{2}{5}\right)\)
c, \(\left(\dfrac{11}{24}:\dfrac{55}{36}\right).\dfrac{10}{3}\)
d, \(\left(\dfrac{1}{2}-1\right).\left(\dfrac{1}{3}-1\right)...\left(\dfrac{1}{2017}-1\right)\)
e,\(\left(\dfrac{2}{3}\right):\left(\dfrac{4}{9}\right)^{10}\)
f,\(\left(\dfrac{1}{7}\right)^7.7^7\)
g, \(\dfrac{\left(125\right)^5}{5^{15}}\)
2 tìm x, biết
a, \(\dfrac{-4}{7}-x=\dfrac{5}{7}\)
b, \(x:\left(\dfrac{-3}{8}\right)=\dfrac{1}{2}\)
c, \(\dfrac{-3}{5}+\dfrac{1}{4}:x=\dfrac{-2}{5}\)
d, \(\left(x-\dfrac{2}{5}\right).\left(x+\dfrac{3}{7}\right)=0\)
e, \(\left(x+1\right)^5=-32\)
f, \(x-\left(1,5-7\right)=0,35\)
3 tìm số tự nhiên n biết
a, \(3^n=81\)
b, \(2^n=16\)
c, \(2.2^n=16\)
d, \(2.8^n=128\)
5 so sánh
a, \(2^{333}\) và \(3^{222}\)
b, \(\left(\dfrac{-1}{16}\right)^{100}\) và \(\left(\dfrac{-1}{2}\right)^{400}\)
Tìm x
a) \(\left(\dfrac{3}{5}x-\dfrac{2}{3}x-x\right)\cdot\dfrac{1}{7}=-\dfrac{5}{21}8\)
b) \(\left(5x-1\right)\cdot\left(2x+\dfrac{1}{3}\right)=0\)
c) \(\dfrac{5\left|x+1\right|}{2}=\dfrac{90}{\left|x+1\right|}\)