\(\dfrac{2x-1}{-3x+2}\) = 0
1).(4-3x)(10-5x)=0 2).(7-2x)(4+8x)=0 3).(9-7x)(11-3x)=0
4).(7-14x)(x-2)=0 5).(\(\dfrac{7}{8}\)-2x)(3x+\(\dfrac{1}{3}\))=0 6).3x-2x\(^2\)
7).5x+10x\(^2\)
1.
<=> \(\left[{}\begin{matrix}4-3x=0\\10-5x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{4}{3}\\x=2\end{matrix}\right.\)
2.
<=>\(\left[{}\begin{matrix}7-2x=0\\4+8x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{7}{2}\\x=-\dfrac{1}{2}\end{matrix}\right.\)
3.
<=>\(\left[{}\begin{matrix}9-7x=0\\11-3x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{9}{7}\\x=\dfrac{11}{3}\end{matrix}\right.\)
4.
<=>\(\left[{}\begin{matrix}7-14x=0\\x-2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=2\end{matrix}\right.\)
5.
<=>\(\left[{}\begin{matrix}\dfrac{7}{8}-2x=0\\3x+\dfrac{1}{3}=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{7}{16}\\x=-\dfrac{1}{9}\end{matrix}\right.\)
6,7. ko đủ điều kiện tìm
a) \(x\left(x+4\right)-4x+1=0\)
b) \(2\left(x-3\right)+4=2x+2\)
c) \(\dfrac{x+3}{2}-\dfrac{2x+1}{4}=\dfrac{1}{4}\)
d) \(\dfrac{x^2+3x}{x+3}+3=0\)
e) \(x^2-3x\left(x-1\right)-3x-2=0\)
a: =>x^2+4x-4x+1=0
=>x^2+1=0
=>Loại
b: =>2x-6+4=2x+2
=>-2=2(loại)
c: =>2(x+3)-2x-1=1
=>6-1=1
=>5=1(loại)
d =>x+3=0
=>x=-3(loại)
e: =>x^2-3x^2+3x-3x-2=0
=>-2x^2-2=0
=>x^2+1=0
=>Loại
Giair các phương trình sau
\(a,\dfrac{3x^2+7x-10}{x}=0\) \(b,\dfrac{4x-17}{2x^2+1}=0\) \(c,\dfrac{\left(x^2+2x\right)-\left(3x-6\right)}{x+2}=0\)
\(d,\dfrac{x^2-x-6}{x-3}=0\) \(e,\dfrac{2x-5}{x+5}=3\) \(f,\)\(\dfrac{5}{3x+2}=2x-1\)
\(g,\dfrac{x^2-6}{x}=x+\dfrac{3}{2}\) \(h,\dfrac{4}{x-2}-x+2=0\)
Giups mình với , mik đang cần gấp
a) ĐKXĐ: \(x\ne0\)
Ta có: \(\dfrac{3x^2+7x-10}{x}=0\)
Suy ra: \(3x^2+7x-10=0\)
\(\Leftrightarrow3x^2-3x+10x-10=0\)
\(\Leftrightarrow3x\left(x-1\right)+10\left(x-1\right)=0\)
\(\Leftrightarrow\left(x-1\right)\left(3x+10\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-1=0\\3x+10=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\\3x=-10\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\\x=-\dfrac{10}{3}\end{matrix}\right.\)
Vậy: \(S=\left\{1;-\dfrac{10}{3}\right\}\)
a/ \(\dfrac{3x^2+7x-10}{x}=0\)
\(< =>3x^2+7x-10=0\)
\(< =>3x^2+10x-3x-10=0\)
\(< =>\left(3x^2+10x\right)-\left(3x+10\right)=0\)
\(< =>x\left(3x+10\right)-\left(3x+10\right)=0\)
\(< =>\left(3x+10\right)\left(x-1\right)=0\)
\(=>\left\{{}\begin{matrix}3x+10=0=>x=-\dfrac{10}{3}\\x-1=0=>x=1\end{matrix}\right.\)
Vậy tập nghiệm của .....
Giải phương trình:
a) \(\dfrac{x^2-x-6}{x-3}=0\)
b) \(\dfrac{x+5}{3x-6}-\dfrac{1}{2}=\dfrac{2x-3}{2x-4}\)
c) \(\dfrac{12}{1-9x^2}=\dfrac{1-3x}{1+3x}-\dfrac{1+3x}{1-3x}\)
d) \(\dfrac{x+5}{x-1}=\dfrac{x+1}{x-3}-\dfrac{8}{x^2-4x+3}\)
e) \(\dfrac{x+1}{x-2}-\dfrac{5}{x+2}=\dfrac{12}{x^2-4}+1\)Thể loại truyện
a) ĐKXĐ: \(x\ne3\)
Ta có: \(\dfrac{x^2-x-6}{x-3}=0\)
\(\Leftrightarrow\dfrac{\left(x+2\right)\left(x-3\right)}{x-3}=0\)
Suy ra: x+2=0
hay x=-2(thỏa ĐK)
Vậy: S={-2}
d)
ĐKXĐ: \(x\notin\left\{1;3\right\}\)
Ta có: \(\dfrac{x+5}{x-1}=\dfrac{x+1}{x-3}-\dfrac{8}{x^2-4x+3}\)
\(\Leftrightarrow\dfrac{\left(x+5\right)\left(x-3\right)}{\left(x-1\right)\left(x-3\right)}=\dfrac{\left(x+1\right)\left(x-1\right)}{\left(x-3\right)\left(x-1\right)}-\dfrac{8}{\left(x-1\right)\left(x-3\right)}\)
Suy ra: \(x^2-3x+5x-15=x^2-1-8\)
\(\Leftrightarrow2x-15+9=0\)
\(\Leftrightarrow2x-6=0\)
hay x=3(loại)
Vậy: \(S=\varnothing\)
Rút gọn A= \(\dfrac{1}{x}\)-\(\dfrac{x}{2x+1}\)+\(\dfrac{2x^2-3x-1}{x\left(2x+1\right)}\) x≠0,\(\dfrac{1}{2}\),1
Help
\(A=\dfrac{2x+1}{x\left(2x+1\right)}-\dfrac{x^2}{x\left(2x+1\right)}+\dfrac{2x^2-3x-1}{x\left(2x+1\right)}\)
\(=\dfrac{2x+1-x^2+2x^2-3x-1}{x\left(2x+1\right)}\)
\(=\dfrac{x^2-x}{x\left(2x+1\right)}=\dfrac{x\left(x-1\right)}{x\left(2x+1\right)}\)
\(=\dfrac{x-1}{2x+1}\)
\(=\dfrac{2x+1}{x\left(2x+1\right)}-\dfrac{x^2}{x\left(2x+1\right)}+\dfrac{2x^2-3x-1}{x\left(2x+1\right)}\)
\(=\dfrac{2x+1-x^2+2x^2-3x-1}{x\left(2x+1\right)}\)
\(=\dfrac{x^2+x}{x\left(2x+1\right)}\)
\(=\dfrac{x-1}{2x+1}\).
Giải các phương trình sau
\(1,\dfrac{3x-1}{4}+\dfrac{6x-2}{8}=\dfrac{1-3x}{6}\)
\(2,\left(2x-1\right)^2+\left(x-3\right)\left(2x-1\right)=0\)
1: \(\Leftrightarrow6\left(3x-1\right)+3\left(6x-2\right)=4\left(1-3x\right)\)
=>18x-6+18x-6=4-12x
=>36x-12=4-12x
=>48x=16
hay x=1/3
2: \(\Leftrightarrow\left(2x-1\right)\left(2x-1+x-3\right)=0\)
=>(2x-1)(3x-4)=0
=>x=1/2 hoặc x=4/3
giải các phương trình sau
a, 3x -(3x+2) =x+3
b, \(\dfrac{5x-1}{4}+\dfrac{2x-1}{3}=\dfrac{3x}{2}\)
c, \(\left(x^2-3^2\right)+2\left(x-3\right)=0\)
d,\(\dfrac{1}{x-1}+\dfrac{2}{1+x}-\dfrac{4x+6}{x^2-1}=0\)
a: Ta có: \(3x-\left(3x+2\right)=x+3\)
\(\Leftrightarrow x+3=-2\)
hay x=-5
b: Ta có: \(\dfrac{5x-1}{4}+\dfrac{2x-1}{3}=\dfrac{3x}{2}\)
\(\Leftrightarrow15x-3+8x-4=18x\)
\(\Leftrightarrow5x=7\)
hay \(x=\dfrac{7}{5}\)
giải các bpt sau
a,\(\dfrac{x^2+2x-13}{x-1}< 1\)
b,\(\dfrac{3x^2+x-4}{x-1}< 3\)
c,\(\dfrac{2x^2-3x+1}{x+2}>0\)
d,\(\dfrac{x^2-x-6}{x^2-1}\le1\)
a: =>\(\dfrac{x^2+2x-13-x+1}{x-1}< 0\)
=>\(\dfrac{x^2+x-12}{x-1}< 0\)
=>\(\dfrac{\left(x+4\right)\left(x-3\right)}{x-1}< 0\)
=>1<x<3 hoặc x<-4
b: =>\(\dfrac{3x^2+4x-3x-4}{x-1}< 3\)
=>3x+4<3
=>3x<-1
=>x<-1/3
c: TH1: 2x^2-3x+1>0 và x+2>0
=>(2x-1)(x-1)>0 và x+2>0
=>x>1
TH2: (2x-1)(x-1)<0 và x+2<0
=>x<-2 và 1/2<x<1
=>Loại
1 Giải các bất PT sau
a) (2x+1)2-(x+2)2>0
b)\(\dfrac{5x^2-3x}{5}+\dfrac{3x+1}{4}< \dfrac{x\left(2x+1\right)}{2}-\dfrac{3}{2}\)
c) \(\dfrac{-1}{2x+3}< 0\)
a) \(\left(2x+1\right)^2-\left(x+2\right)^2>0\)
\(\Leftrightarrow\left(2x+1-x-2\right)\left(2x+1+x+2\right)>0\)
\(\Leftrightarrow\left(x-1\right)\left(3x+3\right)>0\)
\(\Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x-1>0\\3x+3>0\end{matrix}\right.\\\left\{{}\begin{matrix}x-1< 0\\3x+3< 0\end{matrix}\right.\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x>1\\x>-1\end{matrix}\right.\\\left\{{}\begin{matrix}x< 1\\x< -1\end{matrix}\right.\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x>1\\x< -1\end{matrix}\right.\)
Vậy tập nghiệm của bất phương trình là x > 1 hoặc x < -1
b) Sửa lại rồi làm câu b nèk\(\dfrac{5x-3x}{5}+\dfrac{3x+1}{4}>\dfrac{x\left(2x+1\right)}{2}-\dfrac{3}{2}\)
\(\Leftrightarrow4\left(5x-3x\right)+5\left(3x+1\right)>10\left(x+2x\right)-30\)\(\Leftrightarrow20x-12x+15x+5>10x+20x-30\)\(\Leftrightarrow20x-12x+15x-10x-20x>-30-5\)\(\Leftrightarrow-7x>-35\)
\(\Leftrightarrow x< 5\)
c) \(\dfrac{-1}{2x+3}< 0\)
dễ nhé mình học bài hóa mai kt 15 phút nên ko có time để giúp
tìm x biết
b, | 4-7x | - \(\dfrac{3}{2}\) : 5 = | -1 \(\dfrac{1}{3}\) |
c,( 7-3x ) ( 2x+ 1) = 0
d, 2x ( 5-3x ) > 0
e, | 3x + 1 | + | 1 - 3x | = 0
g, | 3x + 1 | + | 1-3x | = 0
b) \(\left|4-7x\right|-\dfrac{3}{2}:5=\left|-1\dfrac{1}{3}\right|\)
\(\left|4-7x\right|-\dfrac{3}{10}=\dfrac{4}{3}\)
\(\left|4-7x\right|=\dfrac{49}{30}\) (*)
+) Nếu 4 - 7x \(\ge\) 0 \(\Rightarrow x\le\dfrac{4}{7}\)
PT (*) \(\Leftrightarrow4-7x=\dfrac{49}{30}\)
\(-7x=-\dfrac{71}{30}\)
x = \(\dfrac{71}{210}\) (t/m)
+) Nếu \(4-7x< 0\Rightarrow x>\dfrac{4}{7}\)
Pt (*) \(\Leftrightarrow-4+7x=\dfrac{49}{30}\)
x = \(\dfrac{169}{210}\) (t/m)
Vậy x=\(\dfrac{71}{210}\) hoặc x = \(\dfrac{169}{210}\)