Những câu hỏi liên quan
Thực hiện phép chia
a) (5x^4+3x-1-3x^5):(1+x-x^2)
b) ( 2-4x +3x^4+7x^2-5x^3):(1+x^2-x)
c) ( 17x^2-6x^4+5x^3-23x+7):(7-3x^2-2x)
Làm phép chia
5x4-3x5+3x-1):(x+1-x2)
(2-4x+3x4+7x2-5x3):(1+x2-x)
17x2+6x4+5x3-23x+7):(7-3x2-2x)
(3x4+11x3-5x2-19x+10):(x2+3x-2)
1) Tìm x :
a) 5x3 + 3x2 + 3x + 1 = -23x
b) x3 - 5x2+ 4x -20 = 0
b) \(x^3-5x^2+4x-20=0\)
\(=\left(x^3-5x^2\right)+\left(4x-20\right)=0\)
\(=x^2\left(x-5\right)+4\left(x-5\right)=0\)
\(=\left(x^2+4\right)\left(x-5\right)=0\)
\(x^2\ge0\)
\(\Rightarrow x^2+4\ge4>0\)
\(\Rightarrow x-5=0\)
\(\Rightarrow x=5\)
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1) Tìm x :
a) 5x3 + 3x2 + 3x + 1 = -23x
b) x3 - 5x2 + 4x -20 = 0
Tìm x biết a) (x^2-4x+5)_(x^2-2x+1)=3 lớp 7
b)(4x^3-5X^2+3x-1)+(3-5x+5x^2-4x^3)=2
c)(3x-2)-(5x+4)=(x-3)-(X+5)
a, \(-4x+5+2x-1=3\Leftrightarrow-2x=-1\Leftrightarrow x=\dfrac{1}{2}\)
b, \(-2x+2=2\Leftrightarrow x=0\)
c, \(-2x-6=-8\Leftrightarrow x=1\)
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Bài 1: Rút Gọn
a)(x+7)(x-7)-x2
b)(5x-1)(5x+1)-(25x2+1)
c)(4x+1)(4x-1)-(4x-1)2
d)(3x-5)2-(3x+5)(3x-5)
a) \(=x^2-49-x^2\) \(=-49\)
b) \(=25x^2-1-25x^2-1\) \(=-2\)
c) \(=16x^2-1-16x^2+8x-1\) \(=8x-2\)
d) \(=9x^2-30x+25-9x^2+25\) \(=50-30x\)
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Tìm x:
1/ 4.(18-5x)-12.(3x-7)=15.(2x-16)-6.(x+14) 2/5.(3x+5)-4(2x-3)=5x+3.(2x+12)+1 3/2.(5x-8)-3(4x-5)=4(3x-4)+11 4/5x-3.{4x-2.[4x-3(5x-2)]}=182
a, \(4\left(18-5x\right)-12\left(3x-7\right)=15\left(2x-16\right)-6\left(x+14\right)\)
\(\Rightarrow72-20x-36x+84=30x-240-6x-84\)
\(\Rightarrow-20x-36x-30x+6x=-240-84-72-84\)
\(\Rightarrow-80x=-480\Rightarrow x=6\)
b, \(5\left(3x+5\right)-4\left(2x-3\right)=5x+3\left(2x+12\right)+1\)
\(\Rightarrow15x+25-8x+12=5x+6x+36+1\)
\(\Rightarrow15x-8x-5x-6x=36+1-25-12\)
\(\Rightarrow-4x=0\Rightarrow x=0\)
c, \(2\left(5x-8\right)-3\left(4x-5\right)=4\left(3x-4\right)+11\)
\(\Rightarrow10x-16-12x+15=12x-16+11\)
\(\Rightarrow10x-12x-12x=-16+11+16-15\)
\(\Rightarrow-14x=-4\Rightarrow x=\dfrac{2}{7}\)
d, \(5x-3\left\{4x-2\left[4x-3\left(5x-2\right)\right]\right\}=182\)
\(\Rightarrow5x-3\left[4x-2\left(4x-15x+6\right)\right]=182\)
\(\Rightarrow5x-3\left(4x-8x+30x-12\right)=182\)
\(\Rightarrow5x-12x+24x-90x+36=182\)
\(\Rightarrow-73x=182-36\)
\(\Rightarrow-73x=146\Rightarrow x=-2\)
Chúc bạn học tốt!!!
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2x ^3 -5x^2+4x-1) : (2x+1)
(x63 -2x+4) ; (x+2)
(6x^3 - 19x^2+23x-12):(2x-3)
(x^4 - 2 x ^3 - 1+ 2 x ):(x^2 - 1)
(6x^3 - 5x^2 + 4x -1 ) : (2x^2-x+1)
(x^4 -5x^2+4):(x^2-3x+2)
d: \(\dfrac{x^4-2x^3+2x-1}{x^2-1}\)
\(=\dfrac{\left(x^2-1\right)\left(x^2+1\right)-2x\left(x^2-1\right)}{x^2-1}\)
\(=x^2-2x+1\)
\(=\left(x-1\right)^2\)
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Bài : Rút gọn
1) (3x - 5).(7-5x)-(5x+2).(2-3x)
2) (3x2+5x-2).(2x2-4x+3)
3) (3x2+5x-2).(2x2-4x+3)
4)4(2x3+x)-(2x-1)(4x2+3x+1)
5) 2x(x+3)-(x-5).(7+2x)
Nhanh + đúng auto tick :Đ!
1)6x-8=3x+1
2)12-10x=25-30x
3)3(2x+3)-2(4x-5)=10x+21
4)5(5x-3)-3(2x-4)11-5x
5)4(2-3x)-5(1-2x)=4-6x
6)8(4x-3)-3(2-3x)=13-40x
7)10x-5(1-4x)=5x-11
8)-3(3-4x)-5(4-3x)=12x-50
9)-2(20x-3)-3(4x-5)=9-2(2x-3)
10)-5(2-3x)+3(5-2x)=3x+3(3-5x)
1)6x-8=3x+1
6x-3x=1+8
3x=9
x=3
Vậy x=3
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2: 12-10x=25-30x
=>20x=13
=>x=13/20
3: \(3\left(2x+3\right)-2\left(4x-5\right)=10x+21\)
=>6x+9-8x+10=10x+21
=>10x+21=-2x+19
=>12x=-2
=>x=-1/6
4: \(\Leftrightarrow25x-15-6x+12=11-5x\)
=>19x-3=11-5x
=>24x=14
=>x=7/12
5: \(\Leftrightarrow8-12x-5+10x=4-6x\)
=>4-6x=-2x+3
=>-4x=-1
=>x=1/4
6: \(\Leftrightarrow32x-24-6+9x=13-40x\)
=>41x-30=13-40x
=>81x=43
=>x=43/81
7: \(\Leftrightarrow10x-5+20x=5x-11\)
=>30x-5=5x-11
=>25x=-6
=>x=-6/25
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