2: =>2x-1/4=5/6-1/2x
=>5/2x=5/6+1/4=13/12
=>x=13/30
3: =>3x-5/6=2/3-1/2x
=>3,5x=2/3+5/6=4/6+5/6=9/6=3,2
hay x=32/35
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Bài 1: Thu gọn
a) frac{1}{5}x^4y^3-3x^4y^3
b) 5x^2y^5-frac{1}{4}x^2y^5
c) frac{1}{7}x^2y^3.left(-frac{14}{3}xy^2right)-frac{1}{2}xy.left(x^2y^{text{4}}right)
d) left(3xyright)^2.left(-frac{1}{2}x^3y^2right)
e) -frac{1}{4}xy^2+frac{2}{5}x^2y+frac{1}{2}xy^2-x^2y
f) frac{1}{2}x^4y.left(-frac{2}{3}x^3y^2right)-frac{1}{3}x^7y^3
g) frac{1}{2}x^2y.left(-10x^3yz^2right).frac{1}{4}x^5y^3z
h) 4.left(-frac{1}{2}xright)^2-frac{3}{2}x.left(-xright)+frac{1}{3}x^2
i) 1frac{2}{3}x^3y.left(frac{-1}{2}xy...
Đọc tiếp
Bài 1: Thu gọn
a) \(\frac{1}{5}x^4y^3-3x^4y^3\)
b) \(5x^2y^5-\frac{1}{4}x^2y^5\)
c) \(\frac{1}{7}x^2y^3.\left(-\frac{14}{3}xy^2\right)-\frac{1}{2}xy.\left(x^2y^{\text{4}}\right)\)
d) \(\left(3xy\right)^2.\left(-\frac{1}{2}x^3y^2\right)\)
e) \(-\frac{1}{4}xy^2+\frac{2}{5}x^2y+\frac{1}{2}xy^2-x^2y\)
f) \(\frac{1}{2}x^4y.\left(-\frac{2}{3}x^3y^2\right)-\frac{1}{3}x^7y^3\)
g) \(\frac{1}{2}x^2y.\left(-10x^3yz^2\right).\frac{1}{4}x^5y^3z\)
h) \(4.\left(-\frac{1}{2}x\right)^2-\frac{3}{2}x.\left(-x\right)+\frac{1}{3}x^2\)
i) \(1\frac{2}{3}x^3y.\left(\frac{-1}{2}xy^2\right)^2-\frac{5}{4}.\frac{8}{15}x^3y.\left(-\frac{1}{2}xy^2\right)^2\)
k) \(-\frac{3}{2}xy^2.\left(\frac{3}{4}x^2y\right)^2-\frac{3}{5}xy.\left(-\frac{1}{3}x^4y^3\right)+\left(-x^2y\right)^2.\left(xy\right)^2\)
n) \(-2\frac{1}{5}xy.\left(-5x\right)^2+\frac{3}{4}y.\frac{2}{3}\left(-x^3\right)-\frac{1}{9}.\left(-x\right)^3.\frac{1}{3}y\)
m) \(\left(-\frac{1}{3}xy^2\right)^2.\left(3x^2y\right)^3.\left(-\frac{5}{2}xy^2z^3\right)^{^2}\)
p) \(-2y.\left|2\right|x^4y^5.\left|-\frac{3}{4}\right|x^3y^2z\)
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, \(\frac{-3}{4}-\left|\frac{4}{5}-x\right|=-1\)
Tìm đa thức M , biết :
a) \(M-\left(\frac{1}{2}x^2y-5xy^2+x^3-y^3\right)=\frac{3}{4}xy^2-2x^2y+\)\(2y^3-\frac{1}{3}x^3\)
b)\(\left(-\frac{1}{3}x^3y^3+5x^2y^2-\frac{5}{2}xy\right)-M=xy-\frac{1}{6}x^3y^3-3x^2y^2\)
c)\(\left(\frac{2}{7}xy^4-5x^5+7x^2y^3-3\right)+M=0\)
Bài 1: Thực hiện phép tính
a) 2frac{1}{2}-frac{4}{3}+left(frac{-1}{3}right)^4
b) frac{1}{7}-left(-frac{3}{14}right)+frac{1}{2}
c) -12:left(frac{3}{4}-frac{5}{6}right)^2
d) left(2^2:frac{4}{3}-frac{1}{2}right).frac{6}{5}-17
Bài 2:Tìm x biết
a) frac{4}{7}-xfrac{1}{3}
b) x-frac{2}{3}-frac{6}{7}
c) left|x-5right|7
d) frac{2}{3}-1frac{4}{15}xfrac{-3}{5}
Đọc tiếp
Bài 1: Thực hiện phép tính
a) \(2\frac{1}{2}-\frac{4}{3}+\left(\frac{-1}{3}\right)^4\)
b) \(\frac{1}{7}-\left(-\frac{3}{14}\right)+\frac{1}{2}\)
c) -12:\(\left(\frac{3}{4}-\frac{5}{6}\right)^2\)
d) \(\left(2^2:\frac{4}{3}-\frac{1}{2}\right).\frac{6}{5}-17\)
Bài 2:Tìm x biết
a) \(\frac{4}{7}-x=\frac{1}{3}\)
b) \(x-\frac{2}{3}=-\frac{6}{7}\)
c) \(\left|x-5\right|=7\)
d) \(\frac{2}{3}-1\frac{4}{15}x=\frac{-3}{5}\)
1, tìm x từ tỉ lệ thức sau
a, frac{3x+2}{5x+7}frac{3x-1}{5x-1}
b, frac{37-x}{x+13}frac{3}{7}
c, frac{x+1}{2x+1}frac{0,5.x+2}{x+3}
d, frac{x-2}{x+2}frac{x+3}{x-4}
f,frac{3x-5}{x}frac{9x}{3x+2}
e,frac{x+2}{6}frac{5x-1}{5}
Đọc tiếp
1, tìm x từ tỉ lệ thức sau
a, \(\frac{3x+2}{5x+7}\)=\(\frac{3x-1}{5x-1}\)
b, \(\frac{37-x}{x+13}\)=\(\frac{3}{7}\)
c, \(\frac{x+1}{2x+1}\)=\(\frac{0,5.x+2}{x+3}\)
d, \(\frac{x-2}{x+2}\)=\(\frac{x+3}{x-4}\)
f,\(\frac{3x-5}{x}\)=\(\frac{9x}{3x+2}\)
e,\(\frac{x+2}{6}\)=\(\frac{5x-1}{5}\)
tìm x biết
a.\(\frac{-3}{4}-\left|\frac{4}{5}-x\right|=-1\)
b.\(\left|\frac{-1}{2}-x\right|=\frac{1}{3}\)
c.\(\left|2^1_2+x\right|-\frac{-2}{3}=3\)
d.\(\frac{-5}{7}-\left|\frac{1}{2}-x\right|=\frac{-11}{4}\)
e.\(\left|3x+4\right|=2\left|2x-9\right|\)
Bài 1: Tìm x:
a) \(\frac{6x+5}{2}-\left(2x+\frac{2x+1}{2}\right)=\frac{10x+3}{4}\)
b) \(\frac{3.\left(2x+1\right)}{4}-\frac{5x+3}{6}+\frac{x+1}{3}=x+\frac{7}{12}\)
GIÚP MIK NHA!! MIK ĐAG CẦN GẤP
Tìm x : \(\left|\frac{3}{4}+\frac{1}{4}:x\right|=\frac{2}{5}\)
b) \(\frac{2}{3}x-1\frac{2}{5}=\frac{1}{2}x+0,8\)
c) \(\left|2x-1\right|-x=1\)
Tìm x, biết:
a) 4left|3x-1right|+left|xright|-2left|x-5right|+7left|x-3right|12
b) 3left|x+4right|-left|2x+1right|-5left|x+3right|+left|x+9right|5
c)
left|2frac{1}{5}-xright|+left|x-frac{1}{5}right|+8frac{1}{5}1,2
d) 2left|x+3frac{1}{2}right|+left|xright|-3frac{1}{2}left|2frac{1}{5}-xright|
Đọc tiếp
Tìm \(x,\) biết:
a) \(4\left|3x-1\right|+\left|x\right|-2\left|x-5\right|+7\left|x-3\right|=12\)
b) \(3\left|x+4\right|-\left|2x+1\right|-5\left|x+3\right|+\left|x+9\right|=5\)
c) \( \left|2\frac{1}{5}-x\right|+\left|x-\frac{1}{5}\right|+8\frac{1}{5}=1,2\)
d) \(2\left|x+3\frac{1}{2}\right|+\left|x\right|-3\frac{1}{2}=\left|2\frac{1}{5}-x\right|\)