Chứng minh \(F=\frac{3}{2}\cdot x^4-\frac{1}{16}\cdot x^4+\frac{1}{32}\cdot x^4-\frac{1}{4}\cdot x^4>0\)với mọi x khác 0
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
\(\frac{1}{3}\cdot x-\frac{2}{5}\cdot\left(x+1\right)=0\)
\(\frac{3}{4}+\frac{1}{4}\cdot x=\frac{1}{2}+\frac{1}{2}\cdot x\)
\(\frac{x+2}{0,5}=\frac{2\cdot x+1}{2}\)
đề bài là j vậy bạn
Vương Gia Huy tìm x bạn ơi
\(\left(\frac{1}{7}\cdot x-\frac{2}{7}\right)\cdot\left(-\frac{1}{5}\cdot x+\frac{3}{5}\right)\cdot\left(\frac{1}{3}\cdot x+\frac{4}{3}\right)=0\)
( 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 :
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
Tìm X
\(\frac{1}{4}\cdot\frac{2}{6}\cdot\frac{3}{8}\cdot\frac{4}{10}\cdot\frac{5}{12}\cdot.......\cdot\frac{30}{62}\cdot\frac{31}{64}=4^x\)
1/4.2/6.3/8.4/10.........30/62.31/64=4x
=1/2.1/2.1/2.1/2.............1/2.1/64=4^x
=1/2^30.1/2^6=4^x
=1/2^36=4^x
=1/4^18=4^x
=>x=-18
Bai1:tìm x biết
a, (\(\frac{1}{7}\)\(\cdot\) x -\(\frac{2}{7}\))(-\(\frac{1}{5}x+\frac{3}{5}\))(\(\frac{1}{3}\cdot x+\frac{4}{3}\))
b, \(\frac{1}{6}\cdot x+\frac{1}{10}\cdot x-\frac{4}{5}\cdot x+1=0\)
c,(\(x-\frac{2}{9}\))^3=(\(\frac{2}{3}\))^6
d, (x-7)^x+1-(x-7)^x+11=0
Tìm x
a, \(\left(x-1\right)^{x+2}=\left(x-1\right)^{x+4}\)
b,\(\frac{1}{4}\cdot\frac{2}{6}\cdot\frac{3}{8}\cdot\frac{4}{10}\cdot\frac{5}{12}.....\frac{30}{62}\cdot\frac{31}{64}=2^x\)
a)\(\left(x-1\right)^{x+2}=\left(x-1\right)^{x+4}\Leftrightarrow\left(x-1\right)^{x+2}\left[\left(x-1\right)^2-1\right]=0\Leftrightarrow x\left(x-1\right)^{x+2}\left(x-2\right)=0\)
Do đó \(x\in\left\{0;1;2\right\}\)
b)
\(\frac{1}{4}\cdot\frac{2}{6}\cdot\frac{3}{8}\cdot...\cdot\frac{31}{64}=2^x\Leftrightarrow\frac{1\cdot2\cdot3\cdot...\cdot31}{4\cdot6\cdot8\cdot...\cdot64}=2^x\Leftrightarrow\frac{31!}{\left(2\cdot2\right)\cdot\left(2\cdot3\right)\cdot\left(2\cdot4\right)\cdot...\cdot\left(2\cdot31\right)\cdot64}=2^x\)
\(\frac{31!}{2^{30}\cdot31!\cdot2^6}=2^x\Leftrightarrow\frac{1}{2^{36}}=2^x\Leftrightarrow2^{-36}=2^x\Rightarrow x=-36\)
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 \(\frac{1}{4}\cdot x+\frac{3}{4}\cdot\left(x+1\right)=0\)
\(\frac{1}{4}.x+\frac{3}{4}.\left(x+1\right)=0\)
\(\Rightarrow\frac{1}{4}.x+\frac{1}{4}.3.\left(x+1\right)=0\)
\(\Rightarrow\frac{1}{4}.\left[x+3.\left(x+1\right)\right]=0\)
\(\Rightarrow x+3.\left(x+1\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x=0\\3\left(x+1\right)=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=0\\x+1=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=0\\x=-1\end{cases}}\)
Vậy \(\orbr{\begin{cases}x=0\\x=-1\end{cases}}\)
Chúc bạn học tốt !!!
Dấu \(\orbr{\begin{cases}\\\end{cases}}\)là dấu hoặc nhé !!!