Xét:|2x+4|+|2x+6|+|2x+8|\(\ge\)0
Mà |2x+4|+|2x+6|+|2x+8|\(\ge\)18
Vậy GTNN của |2x+4|+|2x+6|+|2x+8|=18
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Các câu hỏi tương tự
Bài 5: Tìm x biết:
a) \(\left(2x-1\right)^4=16\)
b) \(\left(2x+1\right)^4=\left(2x+1\right)^6\)
c) \(\left||x+3\right|-8|=20\)
Tìm x, biết:
1) left|4xright|3x+12 7) left|5xright|-3x-20
2) left|2x+4right|2x-5 8) x-5x+left|-2xright|-30
3)left|x+3right|3x-1 9) left|3-xright|+x^2-left(4+xright)x0
4) left|x-4right|+3x5
5)left|x-5right|3x
6) left|x+2right|2x-10
Đọc tiếp
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) \(\left|x+2\right|=2x-10\)
Rút gọn biểu thức:
a, \(\left(2x+1\right)^2+\left(2x-1\right)^2-2\left(1+2x\right)\left(2x-1\right)\)
\(b,\left(x-1\right)^3-\left(x+2\right)\left(x^2-2x+4\right)+3\left(x-1\right)\left(x+1\right)\)
Tìm x:
\(3\left|x+4\right|-\left|2x+1\right|-5\left|x+3\right|+\left|x-9=5\right|\)
\(\left|x-2\right|+\left|x-3\right|+\left|2x-8\right|=9\\ \left|x+2\right|+\left|x+3\right|+\left|x+1\right|=4\\ \left|x+\dfrac{1}{1.5}\right|+\left|x+\dfrac{1}{5.9}\right|+\left|x+\dfrac{1}{9.13}\right|+...+\left|x+\dfrac{1}{397.401}\right|=101x\)
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 :
a, \(\left|3x+8\right|=2x+4\)
b, \(2\left|2x+1\right|-x=15\)
c, \(\left|3x+7\right|=3x+7\)
d, \(\left|2x-5\right|+2x=5\)
thực hiện phép tính
a.5x^2-3xleft(x+2right)
b.3xleft(x-5right)-5xleft(x+7right)
c.3x^2y.left(2x^2-yright)-2x^2.left(2x^2y-y^2right)
d.3x^2.left(2y-1right)-left[2x^2.left(5y-3right)-2x.left(x-1right)right]
e.4xleft(x^3-4x^2right)+2xleft(2x^3-x^2+7xright)
f.25x-4left(3x-1right)+7xleft(5-2x^2right)
Đọc tiếp
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.\(25x-4\left(3x-1\right)+7x\left(5-2x^2\right)\)
\(2\left|2x-6\right|=\dfrac{5}{6}-\left|x-3\right|\)
2:\(\left|x+2013\right|+\left|x+2014\right|+\left|x+2045\right|=2\)
3:\(\left|2x-1\right|=\left|x+1\right|\)
4:\(\sqrt{\left(x+\sqrt{5}\right)}+\sqrt{\left(y-\sqrt{3}\right)^2}+\left|x-y-z\right|=0\)
\(\left|2x+3\right|+\left|2x-1\right|=\dfrac{8}{2\left(y-5\right)^2+2}\)