tìm X
2/3 x X - 1/4 : ( 11/2 -3/4 ) = 0,25 x 2/3
Những câu hỏi liên quan
Tìm x
a)(2x+1)2-4(x+2)2 =9
b)(3x-1)2 +2(x+3)2 +11(x+1)(1-x)=6
c)(x+1)3 - x2 (x+3)=2
d)(x-2)3 -x(x+1)(x-1)+6x2 =5
e)(x-3)(x2 +3x +9)-x(x+4)(x-4)=5
g)(x-2)3 -(x+5)(x2 -5x+25)+6x2 =11
\(\left(2x+1\right)2-4\left(x+2\right)2=9\)
\(4x+2-8x-16=9\)
\(4x-8x=9+16-2\)
\(-4x=23\)
\(x=-\frac{23}{4}\)
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a, \(\left(2x+1\right)2-4\left(x+2\right)2=9\)
\(\Leftrightarrow4x+2-8x-16=0\Leftrightarrow-4x-14=0\Leftrightarrow x=-\frac{7}{2}\)
b, \(\left(x+1\right)3-2x\left(x+3\right)=2\)
\(\Leftrightarrow3x+3-2x^2-6x=2\Leftrightarrow-3x+1-2x^2=0\)
Tìm x ∈ Z sao cho:
a. (3x + 4) ⋮ (x – 3) (x ≠ 3)
b. (x2 + 3x – 13) ⋮ (x + 3) (x ≠ -3)
c. (x2 + 3) ⋮ (x -1) (x ≠ 1)
d. (x2 + 2x – 11) ⋮ (x + 2) (x ≠ -2)
help me plz
Tìm x, biết :
a) (x+4)2-x2(x+12)=16
c) (x+3)3-x(3x+1)2+(2x+1)(4x2-2x+1)=28
d) (x-2)3-(x+5)(x2-5x+25)-6x2=11
c: Ta có: \(\left(x+3\right)^3-x\left(3x+1\right)^2+\left(2x+1\right)\left(4x^2-2x+1\right)=28\)
\(\Leftrightarrow x^3+9x^2+27x+27-9x^3-6x^2-x+8x^3+1=28\)
\(\Leftrightarrow3x^2+26x=0\)
\(\Leftrightarrow x\left(3x+26\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-\dfrac{26}{3}\end{matrix}\right.\)
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\(a,\Leftrightarrow x^2+8x+16-x^3-12x^2=16\\ \Leftrightarrow x^3+11x^2-8x=0\\ \Leftrightarrow x\left(x^2+11x-8\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x^2+11x-8=0\left(1\right)\end{matrix}\right.\\ \Delta\left(1\right)=121+32=153\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{-11-3\sqrt{17}}{2}\\x=\dfrac{-11+3\sqrt{17}}{2}\end{matrix}\right.\\ S=\left\{0;\dfrac{-11-3\sqrt{17}}{2};\dfrac{-11+3\sqrt{17}}{2}\right\}\)
\(c,\Leftrightarrow x^3+9x^2+27x+27-9x^3-6x^2-x+8x^3+1=28\\ \Leftrightarrow3x^2+26x=0\\ \Leftrightarrow x\left(3x+26\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x=-\dfrac{26}{3}\end{matrix}\right.\\ d,\Leftrightarrow x^3-6x^2+12x-8-x^3-125-6x^2=11\\ \Leftrightarrow-12x^2+12x-144=0\\ \Leftrightarrow x^2-x+12=0\Leftrightarrow\left[{}\begin{matrix}x=4\\x=3\end{matrix}\right.\)
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1.Tìm x biết
a, 12 . ( x - 1 ) = 0
b, 3/5x - 3/4 = ( - 3 )2 - | - 11|
c, 4 . ( x - 5/8 ) - 3/4 = 0,25
2. Tìm một số, biết 3/5 của nó bằng 27
a)12(x-1)=0
=>x-1=0
=>x=1
b) 3/5x-3/4=(-3)2-|-11|
3/5x-3/4=9-11=-2
3/5x=-2+3/4=-5/4
=>x=-5/4:3/5=-25/12
c)4(x-5/8)-3/4=0,25
4(x-5/8)=0,25+3/4=1
=>x-5/8=1/4
x=1/4+5/8=7/8
2) Số đó là
27:3/5=45
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mn giải giúp mk bài này vs
1) Tính
a;11/125-17/18-5/7+4/9+17/14
b;1-1/2+2-2/3+3-3/4+4-1/4-3-1/3-2-1/2-1
c;26:[3:0,1/25*2+0,25*4/6,84:3,42
2)Tìm x,Biết
a)x+1/3=2/5-1/3
b)3/7-x=1/4-(-3/5)
c)11/33-(5/42-x)=-(15/28-11/3)
d)|x+4/5|-|-3,75|=-|-2,15|
1. (x-6)^2 = 2(x-6)
2. 2(x-3)^2 = (x-3)(x+5)
3. 4(x-3)=2x-5(2x+3)
4. x2 +4 -2 (x-1) = (x-2)^2
5. x-3/5 = 6 - 1-2x/3
6. x+2 = 6-5x/2
7. x+2/5 - x+3 = x-2/2
8. 2x-5/x-4 = 2x+1/x+2
9. X+3/x-3 - x-1/x+3 = x2 + 4x + 6/x2 -9
10. 3x-3/x2-9 -1/x-3 = x+1/x+3
11. X+1/x-1 - x-1/x+1 = 4/x2 -1
Bài dài quá, lần sau chia nhỏ câu hỏi nhé!!!!!
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Tìm x
a)(2x+1)2-4(x+2)2 =9
b)(3x-1)2 +2(x+3)2 +11(x+1)(1-x)=6
c)(x+1)3 - x2 (x+3)=2
d)(x-2)3 -x(x+1)(x-1)+6x2 =5
e)(x-3)(x2 +3x +9)-x(x+4)(x-4)=5
g)(x-2)3 -(x+5)(x2 -5x+25)+6x2 =11
Tìm x, biết:
a, 11/13 - ( 5/42 -x ) = - ( 5/28 - 11/13 )
b, | x + 4/15 | - | - 3,75 | = -| -2,15 |
c, ( 0,25 - 30% x ) . 1/3 = 1/4 - 31/6
d, ( x - 1/2 ) : 1/3 + 5/7 = 68/7
a, 11/13 - ( 5/42 - x ) = - (5/28 - 11/13)
11/13 - (5/42 - x) = - 5/28 + 11/13
- (5/42 - x) + 5/28 = -11/13 + 11/13
- 5/42 + x + 5/28 = 0
- 5/42 + x = 0 - 5/28
- 5/42 + x = - 5/28
x = -5/28 +5/42
x = - 5/84
b, / x + 4/15 \ - / - 3,75 \ = - / - 2,15 \
./ x + 4/15 \ - 3,75 = - 2,15
/ x + 4/15 \ = -2,15 + 3,75
/ x + 4/15 \ = 1,6
x + 4 / 15 = 1,6 hoặc x+ 4/15 = - 1,6
x = 1,6 - 4/15 x = - 1,6 -4/15
x = 4/3 x = -28/15
Vậy x = 4/3 hoặc x = - 28/15
c, ( 0,25 - 30% x ) . 1/3 = 1/4 - 31/6
( 1/4 - 3/10 x ) . 1/3 = - 59/12
( 1/4 - 3/10 x ) = - 59/12 : 1/3
1/4 - 3/10 x = - 59/4
3/10 x = 1/4 + 59/4
3/10 x = 15
x = 15 : 3/10
x = 50
d, ( x - 1/2 ) : 1/3 + 5/7 = 68/7
( x - 1/2 ) : 1/3 = 68/7 - 5/7
( x - 1/2 ) : 1/3 = 63/7
( x - 1/2 ) = 63/7 . 1/3
x -1/2 = 3
x = 3 + 1/2
x = 7/2
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1) 5(x-3) (x-7)-(5x+1) (x-2)= -8
2) x(x+1) (x+2)-(x+4) (3x-5)= 84-5x
3) (9x2-5) (x+3)-3x2(3x+9)=(x-5) (x+4)-x(x-11)
4) (x2-4x+16) (x+4)-x(x+1) (x+2)+3x2=0
5) (8x+2) (1-3x)+(6x-1) (4x-10)=-50
6) (x2+2x+4) (2-x)+x(x-3) (x+4)-x2+24=0
7) (\(\dfrac{x}{2}\)+3) (5-6x)+(12x-2) (\(\dfrac{x}{4}\)+3)=0
1) Ta có: \(5\left(x-3\right)\left(x-7\right)-\left(5x+1\right)\left(x-2\right)=-8\)
\(\Leftrightarrow5\left(x^2-10x+21\right)-\left(5x^2-10x+x-2\right)=-8\)
\(\Leftrightarrow5x^2-50x+105-5x^2+9x+2+8=0\)
\(\Leftrightarrow-41x=-115\)
hay \(x=\dfrac{115}{41}\)
2) Ta có: \(x\left(x+1\right)\left(x+2\right)-\left(x+4\right)\left(3x-5\right)=84-5x\)
\(\Leftrightarrow x\left(x^2+3x+2\right)-\left(3x^2+7x-20\right)=84-5x\)
\(\Leftrightarrow x^3+3x^2+2x-3x^2-7x+20-84+5x=0\)
\(\Leftrightarrow x^3=64\)
hay x=4
3) Ta có: \(\left(9x^2-5\right)\left(x+3\right)-3x^2\left(3x+9\right)=\left(x-5\right)\left(x+4\right)-x\left(x-11\right)\)
\(\Leftrightarrow9x^3+27x^2-5x-15-9x^3-27x^2=x^2-x-20-x^2+11x\)
\(\Leftrightarrow-5x-15=10x-20\)
\(\Leftrightarrow-5x-10x=-20+15\)
\(\Leftrightarrow x=\dfrac{-5}{-15}=\dfrac{1}{3}\)
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