tìm x, biết \(\frac{1}{4}\cdot x+\frac{3}{4}\cdot\left(x+1\right)=0\)
TÌM x
\(\left(\left(\frac{3}{4}\cdot x+5\right)-\left(\frac{2}{3}\cdot x-4\right)-\left(\frac{1}{6}\cdot x+1\right)\right)=\left(\frac{1}{3}\cdot x+4\right)-\left(\frac{1}{3}-3\right)\)
\(\Rightarrow\frac{3}{4}x+5-\frac{2}{3}x+4-\frac{1}{6}x-1=\frac{1}{3}x+4-\frac{1}{3}+3\)+3
\(\Rightarrow\left(\frac{3}{4}x-\frac{2}{3}x-\frac{1}{6}x\right)+\left(5+4-1\right)=\frac{1}{3}x+\left(4-\frac{1}{3}+3\right)\)
=>\(\frac{-1}{12}x+8=\frac{1}{3}x+\frac{20}{3}\)\(\Rightarrow\frac{-1}{12}x+8-\frac{1}{3}x=\frac{20}{3}\)
\(\Rightarrow\left(\frac{-1}{12}-\frac{1}{3}\right)x+8=\frac{20}{3}\)
\(\Rightarrow\frac{-5}{12}x+8=\frac{20}{3}\Rightarrow\frac{-5}{12}x=\frac{20}{3}-8\)
\(\Rightarrow\frac{-5}{12}x=\frac{-4}{3}\Rightarrow x=\frac{-4}{3}:\frac{-5}{12}=\frac{16}{5}\)
Tìm x, biết :
\(\left(3-\frac{1}{2}\cdot x\right)\cdot\left(\left|x+\frac{3}{4}\right|-\frac{5}{6}\right)=0\)
\(\left(3-\frac{1}{2}x\right)\left(\left|x+\frac{3}{4}\right|-\frac{5}{6}\right)=0\)
\(\Rightarrow\orbr{\begin{cases}3-\frac{1}{2}x=0\\\left|x+\frac{3}{4}\right|-\frac{5}{6}=0\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}\frac{1}{2}x=3\\\left|x+\frac{3}{4}\right|=\frac{5}{6}\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}x=6\\x=\frac{1}{12}\\x=\frac{-19}{12}\end{cases}}\)
\(\left(3-\frac{1}{2}x\right)\cdot\left(\left|x+\frac{3}{4}\right|-\frac{5}{6}\right)=0\)
\(\Rightarrow\hept{\begin{cases}3-\frac{1}{2}x=0\\\left|x+\frac{3}{4}\right|-\frac{5}{6}=0\end{cases}}\)
\(\Rightarrow\hept{\begin{cases}x=6\\x+\frac{3}{4}=\pm\frac{5}{6}\end{cases}}\)
Ta có
\(x+\frac{3}{4}=\pm\frac{5}{6}\)
\(\hept{\begin{cases}x+\frac{3}{4}=\frac{5}{6}\\x+\frac{3}{4}=-\frac{5}{6}\end{cases}\Rightarrow\hept{\begin{cases}x=\frac{1}{12}\\x=-\frac{19}{12}\end{cases}}}\)
Vậy \(x\in\left\{3;\frac{1}{2};-\frac{19}{12}\right\}\)
\(\left(3-\frac{1}{2}.x\right).\left(|x+\frac{3}{4}|-\frac{5}{6}\right)=0\)
\(\Rightarrow\orbr{\begin{cases}3-\frac{1}{2}.x=0\\|x+\frac{3}{4}|-\frac{5}{6}=0\end{cases}\Rightarrow\orbr{\begin{cases}\frac{1}{2}.x=3\\|x+\frac{3}{4}|=\frac{5}{6}\end{cases}\Rightarrow}\orbr{\begin{cases}x=6\\x+\frac{3}{4}=\frac{5}{6}\end{cases}\Rightarrow}\orbr{\begin{cases}x=6\\x=\frac{1}{12}\end{cases}}}\)
\(\left(\frac{1}{7}\cdot x-\frac{2}{7}\right)\cdot\left(-\frac{1}{5}\cdot x+\frac{3}{5}\right)\cdot\left(\frac{1}{3}\cdot x+\frac{4}{3}\right)=0\)
( 1/7 . x - 2/7 ) . ( -1.5 . x + 3/5 ) . ( 1/ 3 . x + 4/3) + 0
<=> +) 1/7 . x - 2/7 = 0 +) (- 1 / 5) . x +3/5 = 0 +) 1/ 3 . x + 4/ 3 = 0
x = 2 x = 3 x = 4
Vậy x = 2 : x = 3 ; x=4
Tìm x biết :
a, ( 4x - 9 ) . ( 2,5 + \(\frac{-7}{3}\). x ) = 0
b, \(\frac{1}{x\cdot\left(x+1\right)}\cdot\frac{1}{\left(x+1\right)\cdot\left(x+2\right)}\cdot\frac{1}{\left(x+2\right)\cdot\left(x+3\right)}-\frac{1}{x}=\frac{1}{2015}\)
a)
( 4x - 9 ) ( 2,5 + (-7/3) . x ) = 0
\(\Rightarrow\orbr{\begin{cases}4x-9=0\\2,5+\frac{-7}{3}x=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=\frac{9}{4}\\x=\frac{15}{14}\end{cases}}\)
P/s: đợi xíu làm câu b
b) \(\frac{1}{x\left(x+1\right)}\cdot\frac{1}{\left(x+1\right)\left(x+2\right)}\cdot\frac{1}{\left(x+2\right)\left(x+3\right)}-\frac{1}{x}=\frac{1}{2015}\)
\(\frac{1}{x}-\frac{1}{x+1}+\frac{1}{x+1}-\frac{1}{x+2}+\frac{1}{x+2}-\frac{1}{x+3}-\frac{1}{x}=\frac{1}{2015}\)
\(\frac{-1}{x+3}=\frac{1}{2015}\)
\(\Leftrightarrow x+3=-2015\)
\(\Leftrightarrow x=-2018\)
Vậy,.........
A/ Ta có số nào nhân với 0 cx = 0
Vậy từ đó suy ra 2 trường hợp
TH1\(4x-9=0\)
\(=>x=\frac{9}{4}\)
TH2 \(2,5+-\frac{7}{3}x=0\)
\(=>x=\frac{15}{14}\)
Tìm x,y,z biết :
a)\(\frac{3}{4}\cdot\left(x+\frac{1}{2}\right)=\frac{1}{2}\)
b) \(x\cdot\left(x-\frac{3}{2}\right)=0\)
c)\(|\frac{1}{4}-x|+\frac{2}{3}=\frac{1}{2}\)
d)\(|3\cdot x-2|=|x+1|\)
e)\(|x+\frac{3}{4}|+|x-y|=0\)
g)\(|4\cdot x-2|-2\cdot x=\frac{3}{4}\)
h)\(|5\cdot x+1|-2\cdot x=1\)
i)\((x-\frac{3}{2})\cdot\left(2\cdot x+1\right)>0\)
k)\(|x+\frac{1}{2}|+|x+y+z|+|\frac{1}{3}+y|=0\)
l)\(|2\cdot x-\frac{1}{2}|-\frac{1}{4}=3\)
GIÚP MK VS, CẢM ƠN MỌI NGƯỜI RẤT NHÌU !!!
lam sao bạn viết chữ to như 3/4 . ( x + 1/2 ) vậy
bài 1: tìm x, biết
\(\frac{1}{4}\cdot\frac{2}{6}\cdot\frac{3}{8}\cdot\frac{4}{10}\cdot\cdot\cdot\cdot\cdot\cdot\cdot\cdot\frac{30}{62}\cdot\frac{31}{64}=2^x\)
bài 2:
cho: p = \(\left(x-4\right)^{\left(x-5\right)^{\left(x-6\right)^{\left(x+5\right)}}}\)
tính p(x)=7
giúp mk vs!!!!!
mk cần gấp!!
Bài làm:
Ta có: \(\frac{1}{4}.\frac{2}{6}.\frac{3}{8}.....\frac{30}{62}.\frac{31}{64}=2^x\)
\(\Leftrightarrow\frac{1.2.3.....30.31}{2.2.2.3.2.4.....2.31.2.32}=2^x\)
\(\Leftrightarrow\frac{1}{2^{31}.2^5}=2^x\)
\(\Leftrightarrow\frac{1}{2^{36}}=2^x\)
\(\Rightarrow x=-36\)
mk cần cả giải thích
giúp mk vs!!!
Tìm giá trị của biểu thức : \(C=\frac{4x^4+1}{4\left(x+1\right)^2+1}\cdot\frac{4\left(x+2\right)^4+1}{4\left(x+3\right)^4+1}\cdot\cdot\cdot\frac{4\left(x+10\right)^4+1}{4\left(x+11\right)^4+1}\)
TÌM X
\(\left(\frac{1}{7}x-\frac{2}{7}\right)\cdot\left(-\frac{1}{5}x+\frac{3}{5}\right)\cdot\left(\frac{1}{3}x+\frac{4}{3}\right)=0\)
Vi \(\left(\frac{1}{7}x-\frac{2}{7}\right)\cdot\left(-\frac{1}{5}x+\frac{3}{5}\right)\cdot\left(\frac{1}{3}x+\frac{4}{3}\right)=0\)
\(\Rightarrow\hept{\begin{cases}\frac{1}{7}x-\frac{2}{7}=0\\-\frac{1}{5}x+\frac{3}{5}=0\\\frac{1}{3}x+\frac{4}{3}=0\end{cases}\Rightarrow\hept{\begin{cases}\frac{1}{7}x=\frac{2}{7}\\-\frac{1}{5}x=-\frac{3}{5}\\\frac{1}{3}x=-\frac{4}{3}\end{cases}\Rightarrow}\hept{\begin{cases}x=2\\x=3\\x=-4\end{cases}}}\)
Vậy \(x\in\left\{-4;3;2\right\}\)
\(\Rightarrow\frac{1}{7}x-\frac{2}{7}=0\text{ hoặc }-\frac{1}{5}x+\frac{3}{5}=0\text{ hoặc }\frac{1}{3}x+\frac{4}{3}=0\)
\(\Rightarrow x=2\text{ hoặc }x=3\text{ hoặc }x=-4\)
Vậy tập nghiệm của pt là \(S=\left\{2;3;-4\right\}\)
tìm x :
a, \(\frac{3}{4}\cdot x-\frac{1}{5}=\frac{2}{3}\)
b, \(\frac{2}{5}\cdot\left(x+1\right)-\frac{1}{2}=0\)
c, \(\frac{1}{5}\cdot x-\frac{2}{3}=\frac{4}{8}\)
d, \(\left(x-\frac{2}{3}\right)\cdot\left(1-\frac{4}{16}x\right)=0\)
e, \(\left(0,32-x\right)\cdot\left(4,5-\frac{3}{2}x\right)=0\)
giúp mình với , câu nào các bạn không làm được thì bỏ qua đi
Mấy câu trên dễ rồi mình hướng dẫn bạn làm câu d và e
d)
\(\left(x-\frac{2}{3}\right)\cdot\left(1-\frac{4}{16}x\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x-\frac{2}{3}=0\\1-\frac{1}{4}x=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=\frac{2}{3}\\x=4\end{cases}}\)
Câu e, tương tự nhé bạn
a. \(\frac{3}{4}x-\frac{1}{5}=\frac{2}{3}\)
\(\frac{3}{4}x=\frac{13}{15}\)
\(x=\frac{52}{45}\)
b. \(\frac{2}{5}.\left(x+1\right)-\frac{1}{2}=0\)
\(\frac{2}{5}.\left(x+1\right)=\frac{1}{2}\)
\(x+1=\frac{5}{4}\)
\(x=\frac{1}{4}\)
c.\(\frac{1}{5}.x-\frac{2}{3}=\frac{4}{8}\)
\(\frac{1}{5}.x=\frac{7}{6}\)
\(x=\frac{35}{6}\)
d. \(\left(x-\frac{2}{3}\right).\left(1-\frac{4}{16}x\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x-\frac{2}{3}=0\\1-\frac{4}{16}x=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=0+\frac{2}{3}\\\frac{4}{16}x=1\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=\frac{2}{3}\\x=4\end{cases}}}\)
Vậy x = 2/3 hoặc x = 4
e. \(\left(0,32-x\right).\left(4,5-\frac{3}{2}x\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}0,32-x=0\\4,5-\frac{3}{2}x=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=0,32-0\\\frac{3}{2}x=4,5\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=0,32\\x=3\end{cases}}}\)
Vậy x = 0,32 hoặc x = 3