bài 1:tìm x
a) 3/x+1 = 1/-2
bài 3: tìm x
a)10+3(x-1)=10+6x
b) (x+1) (x-2)=0
a: =>10+3x-3=6x+10
=>3x-3=6x
=>-3x=3
=>x=-1
b: =>x+1=0 hoặc x-2=0
=>x=-1 hoặc x=2
a) \(10+3\left(x-1\right)=10+6x\)
\(\Rightarrow10+3x-3=10+6x\)
\(\Rightarrow3x-6x=10-10+3\)
\(\Rightarrow-3x=3\)
\(\Rightarrow x=-\dfrac{3}{3}\)
\(\Rightarrow x=-1\)
b) \(\left(x+1\right)\left(x-2\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x+1=0\\x-2=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=-1\\x=2\end{matrix}\right.\)
Bài 4: Tìm x
a, (x + 1)2 - x (x - 3) = 2x + 3
b, (x + 2) (x - 3 ) - (x - 3)2 = 15
c, (x + 1)3 -(x3 + 3x2 + 2x - 3) = 0
\(a,\Leftrightarrow x^2+2x+1-x^2+3x-2x=3\\ \Leftrightarrow3x=2\Leftrightarrow x=\dfrac{3}{2}\\ b,\Leftrightarrow x^2-x-6-x^2+6x-9=15\\ \Leftrightarrow5x=30\Leftrightarrow x=6\\ c,\Leftrightarrow x^3+3x^2+3x+1-x^3-3x^2-2x+3=0\\ \Leftrightarrow x=-4\)
a) \(\left(x+1\right)^2-x\left(x-3\right)=2x+3\Rightarrow x^2+2x+1-x^2+3x=2x+3\)
\(\Rightarrow3x=2\Rightarrow x=\dfrac{2}{3}\)
b) \(\left(x+2\right)\left(x-3\right)-\left(x-3\right)^2=15\Rightarrow x^2-3x+2x-6-\left(x^2-6x+9\right)=15\)
\(\Rightarrow5x=30\Rightarrow x=6\)
Bài 2: Tìm x
a) 4x(x-3)+6(3-x)=0 b) x^3-x(x-1)(x+1)=14 c) (x2-x)^2+2(x^2-x)=8
Bài 3:
Bài 2:
a: 4x(x-3)+6(3-x)=0
=>4x(x-3)-6(x-3)=0
=>(x-3)(4x-6)=0
=>\(\left[{}\begin{matrix}x-3=0\\4x-6=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=3\\x=\dfrac{3}{2}\end{matrix}\right.\)
b: \(x^3-x\left(x+1\right)\left(x-1\right)=14\)
=>\(x^3-x\left(x^2-1\right)=14\)
=>\(x^3-x^3+x=14\)
=>x=14
c: \(\left(x^2-x\right)^2+2\left(x^2-x\right)=8\)
=>\(\left(x^2-x\right)^2+2\left(x^2-x\right)-8=0\)
=>\(\left(x^2-x\right)^2+4\left(x^2-x\right)-2\left(x^2-x\right)-8=0\)
=>\(\left(x^2-x\right)\left(x^2-x+4\right)-2\left(x^2-x+4\right)=0\)
=>\(\left(x^2-x+4\right)\left(x^2-x-2\right)=0\)
=>\(\left(x^2-2\cdot x\cdot\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{15}{4}\right)\left(x-2\right)\left(x+1\right)=0\)
=>\(\left(x-2\right)\left(x+1\right)=0\)
=>\(\left[{}\begin{matrix}x-2=0\\x+1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2\\x=-1\end{matrix}\right.\)
Bài 3 tìm x
a) (x-1)(x-5) 3=0
b) 3x^2+7x=10
`3(x-1)(x-5) =0`
`<=> (x-1) =0` hoặc `x-5 = 0`.
`<=> x =1` hoặc `x = 5`.
Vậy `x = 1` hoặc `x = 5.`
`b, 3x^2 + 7x = 10`.
`<=> 3x^2 + 7x - 10 = 0`
`<=> (3x+10)(x-1) =0`
`<=> 3x + 10 = 0` hoặc `x - 1=0`
`<=> x = -10/3` hoặc `x = 1.`
Vậy `x = -10/3` hoặc `x = 1.`
Bài 1: Tìm x
a) (x-4)2-(x-3)(x+3)=5
b) 2x2+4x+2-2y2=0
a: \(\left(x-4\right)^2-\left(x-3\right)\left(x+3\right)=5\)
\(\Leftrightarrow x^2-8x+16-x^2+9=5\)
\(\Leftrightarrow-8x=-20\)
hay \(x=\dfrac{5}{2}\)
Bài 1: Tìm x
a) 3(x-1)^2.3x(x-5)=0
b) (x+3)^2-5x-15=0
c) 2x^5-4x^3+2x=0
a) \(3\left(x-1\right)^2\cdot3x\left(x-5\right)=0\)
\(\Rightarrow9x\left(x-1\right)^2\left(x-5\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x-1=0\\x-5=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=1\\x=5\end{matrix}\right.\)
b) \(\left(x+3\right)^2-5x-15=0\)
\(\Rightarrow\left(x+3\right)^2-5\left(x+3\right)=0\)
\(\Rightarrow\left(x+3\right)\left(x+3-5\right)=0\)
\(\Rightarrow\left(x+3\right)\left(x-2\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x+3=0\\x-2=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=-3\\x=2\end{matrix}\right.\)
c) \(2x^5-4x^3+2x=0\)
\(\Rightarrow2x\left(x^4-2x^2+1\right)=0\)
\(\Rightarrow2x\left[\left(x^2\right)^2-2\cdot x^2\cdot1+1^2\right]=0\)
\(\Rightarrow2x\left(x^2-1\right)^2=0\)
\(\Rightarrow2x\left(x-1\right)^2\left(x+1\right)^2=0\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x-1=0\\x+1=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=1\\x=-1\end{matrix}\right.\)
\(\text{#}Toru\)
bài 1: tìm x
a) 8/23 . 46/24 = 1/3 . x
b) 1/5 : x = 1/5 - 1/7
c) 4/9 - (x - 1/2) mũ 2 = 1/3
d)3,2 . x - (4/5 + 2/3) : 3 2/3 = 7/10
` 8/23 . 46/24 =1/3 .x`
`=>8/23 . 23/12 =1/3 . x`
`=> 1/3 . x=2/3`
`=>x=2/3 : 1/3`
`=>x=2/3 . 3`
`=> x= 6/3`
`=>x=2`
`----`
`1/5 : x= 1/5-1/7`
`=>1/5 : x= 7/35 - 5/35`
`=> 1/5 :x= 2/35`
`=>x= 1/5 : 2/35`
`=>x=1/5 . 35/2`
`=>x=7/2`
`----`
`4/9 - (x-1/2)^2 =1/3`
`=> (x-1/2)^2 =4/9-1/3`
`=> (x-1/2)^2 =4/9- 3/9`
`=> (x-1/2)^2 =1/9`
`=> (x-1/2)^2 = (+- 1/3)^2`
`@ TH1`
`x-1/2=1/3`
`=>x=1/3+1/2`
`=>x= 2/6 + 3/6`
``=>x= 5/6`
`@ TH2`
`x-1/2=-1/3`
`=>x=-1/3 +1/2`
`=>x= -2/6 + 3/6`
`=>x=1/6`
`----`
`3,2 . x-(4/5+2/3) : 3 2/3 = 7/10`
`=> 3,2 . x-22/15 : 11/3 = 7/10`
`=> 3,2 . x-22/15 = 7/10 . 11/3`
`=> 3,2 . x-22/15 =77/30`
`=> 3,2 .x= 77/30 + 22/15`
`=> 3,2 .x=121/30`
`=>x= 121/30. 5/16`
`=>x= 121/96`
bài 1: tìm số hữu tỉ x
a) ( 5x + 3)^2= 25/9
b) ( -1/2x + 3)^3 = -1/125
c) (3^x+1) + 4.3^x = 567
giúp em với ạ :((
a,
\(\left(5x+3\right)^2=\dfrac{25}{9}\\ \Rightarrow\left[{}\begin{matrix}5x+3=\dfrac{5}{3}\\5x+3=-\dfrac{5}{3}\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=-\dfrac{4}{15}\\x=-\dfrac{7}{6}\end{matrix}\right.\)
b,
\(\left(-\dfrac{1}{2}x+3\right)^3=-\dfrac{1}{125}\\ \Rightarrow-\dfrac{1}{2}x+3=-\dfrac{1}{5}\\ \Rightarrow x=\dfrac{32}{5}\)
c,
Bài 1: Tìm x
a) x - 452 = 77 + 48
b) x + 58 = 64 + 58
c) x - 1 - 2 - 3 - 4 = 0
Giúp mình với
a) x - 452 = 77 + 48
x - 452 = 125
x= 125 + 452
x= 577
b) x + 58 = 64 + 58
x + 58 = 122
x= 122 - 58
x= 64
c) x - 1 - 2 - 3 - 4 = 0
x= 0 + 4 + 3 + 2 +1
x= 10
a)x-452=77+48
x-452=125
x=125+452
x=577
b)x+58=64+58
x+58=122
x=122-58
x=64
c)x-1-2-3-4=0
x=0+4+3+2+1
x=10
Nhớ tick cho mk nha^^
bài 1 tìm x
a. 5 - 3(x+4) = -1
b.(x-1) - (x+2) = 0
c.( \(\dfrac{1}{2}\) + x )-( \(\dfrac{1}{3}\) - x) = 0
d. 2x2 - 3 = 5
e. x(2x -1) = 0
g. \(\dfrac{1}{3}\) . x2 - \(\dfrac{1}{6}\)=\(\dfrac{7}{6}\)
a. 5 - 3(x + 4) = -1
⇔ 5 - 3x - 12 = -1
⇔ 3x = -1 - 5 + 12
⇔ 3x = 6
⇔ x = 2
\(d,2x^2-3=5\)
\(\Leftrightarrow2x^2=8\)
\(\Leftrightarrow x^2=4\)
\(\Leftrightarrow x=\pm2\)
\(e,x\left(2x-1\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}2x-1=0\\x=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}2x=1\\x=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=0\end{matrix}\right.\)
a)\(=>3\left(x+4\right)=6=>x+4=2=>x=-2\)
b)\(=>x-1-x-2=0\)
\(=>-3=0\left(vl\right)\) => x ko tồn tại