1. |x -2 |= 2x - 5
=> \(\left[{}\begin{matrix}x-2=-2x+5\\x-2=2x-5\end{matrix}\right.\)
=> \(\left[{}\begin{matrix}3x=7\\x=-5+2\end{matrix}\right.\)( Thực hiện chuyển vế )
=> \(\left[{}\begin{matrix}x=\dfrac{7}{3}\\x=-3\end{matrix}\right.\)
Chắc đúng , bạn kiểm tra nhé !
Chúc bạn học tốt !
Tìm x:
\(3\left|x+4\right|-\left|2x+1\right|-5\left|x+3\right|+\left|x-9=5\right|\)
\(\left|x-2\right|+\left|x-3\right|+\left|2x-8\right|=9\\ \left|x+2\right|+\left|x+3\right|+\left|x+1\right|=4\\ \left|x+\dfrac{1}{1.5}\right|+\left|x+\dfrac{1}{5.9}\right|+\left|x+\dfrac{1}{9.13}\right|+...+\left|x+\dfrac{1}{397.401}\right|=101x\)
thực hiện phép tính
a.\(5x^2-3x\left(x+2\right)\)
b.\(3x\left(x-5\right)-5x\left(x+7\right)\)
c.\(3x^2y.\left(2x^2-y\right)-2x^2.\left(2x^2y-y^2\right)\)
d.\(3x^2.\left(2y-1\right)-\left[2x^2.\left(5y-3\right)-2x.\left(x-1\right)\right]\)
e.\(4x\left(x^3-4x^2\right)+2x\left(2x^3-x^2+7x\right)\)
f.\(25x-4\left(3x-1\right)+7x\left(5-2x^2\right)\)
Rút gọn biểu thức:
a, \(\left(2x+1\right)^2+\left(2x-1\right)^2-2\left(1+2x\right)\left(2x-1\right)\)
\(b,\left(x-1\right)^3-\left(x+2\right)\left(x^2-2x+4\right)+3\left(x-1\right)\left(x+1\right)\)
chứng minh rằng giá trị của các biểu thức sau ko phụ thuộc vào biến
a, \(x^2-2x-\left(3x^2-5x+4\right)+\left(2x^2-3x+7\right)\)
b,\(\left(2x^3-4x^2+x-1\right)-\left(5-x^2+2x^3\right)+3x^2-x\)
c, \(\left(1-x-\dfrac{3}{5}x^2\right)-\left(x^4-2x-6\right)+0,6x^2+x^4-x\)
Tìm x trong các đẳng thức :
\(a.\left|2x-1\right|=\left|2x+3\right|\)
\(b.\left|x-1\right|+3x=1\)
\(c.\left|5x-3\right|-x=7\)
Tìm x biết :
\(\left|x-\dfrac{1}{2}\right|+\left|x-\dfrac{1}{3}\right|+\left|x-\dfrac{1}{4}\right|+....+\left|x-\dfrac{1}{10}\right|=2x\)
Tìm x biết :
\(\left|x-3\right|-2\left|5-2x\right|=11\)
Tìm x, biết:
1) \(\left|4x\right|=3x+12\) 7) \(\left|5x\right|-3x-2=0\)
2) \(\left|2x+4\right|=2x-5\) 8) \(x-5x+\left|-2x\right|-3=0\)
3)\(\left|x+3\right|=3x-1\) 9) \(\left|3-x\right|+x^2-\left(4+x\right)x=0\)
4) \(\left|x-4\right|+3x=5\)
5)\(\left|x-5\right|=3x\)
6) \(\left|x+2\right|=2x-10\)
\(2\left|2x-6\right|=\dfrac{5}{6}-\left|x-3\right|\)
2:\(\left|x+2013\right|+\left|x+2014\right|+\left|x+2045\right|=2\)
3:\(\left|2x-1\right|=\left|x+1\right|\)
4:\(\sqrt{\left(x+\sqrt{5}\right)}+\sqrt{\left(y-\sqrt{3}\right)^2}+\left|x-y-z\right|=0\)
Rút gọn biểu thức:
\(a,\left(x+2\right)\left(x-2\right)-\left(x-3\right)\left(x+1\right)\)
\(b,\left(x-5\right)\left(2x+3\right)-2x\left(x-3\right)+x+7\)
\(c,\left(a+b\right)^2-\left(a-b\right)^2\)
