ĐKXĐ: \(x\ne-3\)
Ta có: \(\frac{x-2}{x+3}=\frac{2}{3}\)
\(\Leftrightarrow3\left(x-2\right)=2\left(x+3\right)\)
\(\Leftrightarrow3x-6=2x+6\)
\(\Leftrightarrow3x-6-2x-6=0\)
\(\Leftrightarrow x-12=0\)
hay x=12(nhận)
Vậy: x=12
\(Tìm\) \(\frac{t}{y}\) :
\(a)\)\(\frac{t}{x}=\frac{4}{3};\frac{y}{z}=\frac{3}{2};\frac{z}{x}=\frac{1}{6}\)
\(b)\frac{t}{x}=\frac{4}{3};\frac{y}{z}=\frac{2}{3};\frac{z}{x}=\frac{1}{6}\)
\(c)\frac{t}{x}=\frac{3}{4};\frac{y}{z}=\frac{3}{2};\frac{z}{x}=\frac{1}{6}\)
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) \(-2y.\left|2\right|x^4y^5.\left|-\frac{3}{4}\right|x^3y^2z\)
Giá trị x thỏa mãn \(\frac{x-3}{2-x}\)=\(\frac{2}{3}\)
tìm x
Tìm x , biết \(\frac{x+2}{327}+\frac{x+3}{326}+\frac{x+4}{325}+\frac{x+5}{324}+\frac{x+349}{5}=0\)
giúp mk vs
Tìm x biết:
a) (x + 1).(x - 2) < 0
b)(x - 2).(x + \(\frac{2}{3}\)) > 0
Tính giá trị các biểu thức sau:
D = \(\frac{-\frac{2}{3}+\frac{3}{4}-2}{\frac{2}{3}-\frac{3}{4}-2}.\frac{\frac{-2}{3}-\frac{3}{4}-2}{\frac{2}{3}+\frac{3}{4}+2}\)
3/a)\(M\left(x\right)=\frac{1}{2}x^2-3x-x^3+3\)
\(=-x^3+\frac{1}{2}x^2-3x+3\)
\(N\left(x\right)=-4x+x^2+\frac{1}{2}x^3+6\)
\(=\frac{1}{2}x^3+x^2-4x^3+6\)
b)Ta có:\(\text{A}\left(x\right)=M\left(x\right)-N\left(x\right)\)
hay \(\text{A}\left(x\right)=\left(-x^3+\frac{1}{2}x^2-3x+3\right)-\left(\frac{1}{2}x^3+x^2-4x+6\right)\)
\(=-x^3+\frac{1}{2}x^2-3x+3-\frac{1}{2}x^3-x^2+4x-6\)
\(=-\frac{3}{2}x^3-\frac{1}{2}x^2+x-3\)
Đặt\(\text{A}\left(x\right)=0\)
\(\Rightarrow-\frac{3}{2}x^3-\frac{1}{2}x^2+x-3=0\)
\(-\frac{3}{2}x^3-\frac{1}{2}x^2=-x+3\)
\(-2\left(x^3-x^2\right)=-x+3\)
\(x^3-x^2+x=3+2=5\)
\(x^2=5\)
\(\Rightarrow x=\sqrt{5}\)
Vậy \(\text{A}\left(x\right)\) có 1 nghiệm là \(\sqrt{5}\)
1) Giá trị \(x\in Z\) để \(\frac{x-5}{7-x}\) là số hữu tỉ dương. x = ?
2) Cặp số nguyên dương chẵn x; y thỏa mãn biểu thức \(\frac{x}{2}+\frac{3}{7}=\frac{5}{4}\). Vậy x = .... ; y = ....
3) Giá trị \(A=\frac{\frac{2}{5}+\frac{2}{7}-\frac{2}{11}}{\frac{3}{5}+\frac{3}{7}-\frac{3}{11}}+\frac{\frac{1}{4}-\frac{1}{5}+\frac{1}{7}}{\frac{3}{4}-\frac{3}{5}+\frac{3}{4}}\)
Cho \(\frac{x+y}{3}=\frac{5-z}{1}=\frac{y+z}{2}=\frac{9+y}{5}\)
a) Tìm x
b) Tìm x+y+z
Câu 1: Tìm x biết: \(\frac{x+2}{327}+\frac{x+3}{326}+\frac{x+4}{325}+\frac{x+5}{324}+\frac{x+349}{5}=0\)
Câu 2: Tìm x biết:\(\frac{x^2-24}{2001}+\frac{x^2-22}{2003}=\frac{x^2-20}{2005}+\frac{x^2-18}{2007}\)
Câu 3: Tìm x biết\(\frac{6}{x^2+2}+\frac{12}{x^2+8}=3-\frac{7}{x^2+3}\)
Câu 4: Tìm x biết: a)\(\frac{x-1}{2001}+\frac{x-2}{2010}-\frac{x-3}{2009}=\frac{x-4}{2008}\)
b)\(\frac{x+97}{125}+\frac{x-63}{35}=\frac{x-7}{21}+\frac{x-77}{49}\)
c)\(\frac{x+2}{13}+\frac{2x+45}{15}=\frac{3x+8}{37}+\frac{4x+69}{9}\)
Giúp mình nhé! Mình cần sự trợ giúp từ các bạn, mình cần phải nộp mấy bài này gấp! Cảm ơn các bạn!!!!!
Tìm x,y,z biết: \(\left|x-\frac{1}{2}\right|+\left|y+\frac{2}{3}\right|+\left|x^2+xz\right|=0\)
