Violympic toán 7
Các câu hỏi tương tự
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) \(\left|x+2\right|=2x-10\)
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.\(25x-4\left(3x-1\right)+7x\left(5-2x^2\right)\)
Tìm x và y biết:
a) \(2\left|2x-3\right|=\frac{1}{2}\)
b) \(7,5-3\left|5-2x\right|=-4,5\)
c) \(\left|3x-4\right|+\left|5-2x\right|=0\)
d) \(\left|x+3\right|+\left|x+1\right|=3x\)
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 biết:
a) \(\left|5x-4\right|=\left|x+2\right|\)
b) \(\left|2+3x\right|=\left|4x-3\right|\)
c) \(\left|2x-3\right|-\left|3x+2\right|=0\)
tìm x biết
a, \(3\left(x-2\right)-4\left(2x+1\right)-5\left(2x+3\right)=50\)
b, \(\left(x-7\right)^5-\left(x-7\right)^3=0\)
tìm x biết
a.\(\left||x+5\right|-4|=3\)
b.8x-\(\left|4x+1\right|\)=x+2
c.\(\left|17x-5\right|-\left|17x+5\right|=0\)
d.\(\left|x-1\right|=2x-5\)
tìm x biết
a) \(\left|2x-1\right|=x+4\) b) \(\left(3x-1\right)^4=81\)
c) \(\left(x-2\right)^3=-64\) d) \(\left|x-3\right|-\left|2x-1\right|=0\)
Bài 1: Tìm x biết:
a, \(x.\cdot\left(\frac{1}{4}+\frac{1}{5}\right)-\left(\frac{1}{7}+\frac{1}{8}\right)=0\)
b, \(\left(5x-1\right).\left(2x-\frac{1}{3}\right)=0\)
c, \(\frac{3x+2}{5x+7}=\frac{3x-1}{5x+1}\)
d, \(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
e, \(\frac{-3}{4}-\left|\frac{4}{5}-x\right|=-1\)