=>(x^2+x+2)(x^2+x+6)=0
=>x^2+x+2=0 hoặc x^2+x+6=0
=>\(x\in\varnothing\)
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Các câu hỏi tương tự
Bài 1: Rút gọn biểu thức
a. \(\left(x-3\right)\left(x+7\right)-\left(x+5\right)\left(x-1\right)\)
b. \(x^2\left(x-4\right)\left(x+4\right)-\left(x^2+1\right)\left(x^2-1\right)\)
Bài 2: Tìm x
a. \(x^2-25-\left(x+5\right)=0\)
b. \(3x\left(x-2\right)-x+2=0\)
c. \(x\left(x-4\right)-2x+8=0\)
Giải các phương trình sau:
a) x^2+dfrac{2x}{x-1}8
b) dfrac{x^2+2x+1}{x^2+2x+2}+dfrac{x^2+2x+2}{x^2+2x+3}dfrac{7}{6}
c) dfrac{x+4}{x-1}+dfrac{x-4}{x+1}dfrac{x+8}{x-2}+dfrac{x-8}{x+2}+6
d) left(x^2+6x+8right)left(x^2+8x+15right)24
e) left(x^2+x-2right)left(x^2+9x+18right)28
f) 3left(-x^2+2x+3right)^4-26x^2left(-x^2+2x+3right)^2-9x^40
g) x^4+6x^3+11x^2+6x+10
h) left(x-3right)left(x-5right)left(x-6right)left(x-10right)-24x^20
i) left(x+2right)^4+left(x+8right)^4272
Đọc tiếp
Giải các phương trình sau:
a) \(x^2+\dfrac{2x}{x-1}=8\)
b) \(\dfrac{x^2+2x+1}{x^2+2x+2}+\dfrac{x^2+2x+2}{x^2+2x+3}=\dfrac{7}{6}\)
c) \(\dfrac{x+4}{x-1}+\dfrac{x-4}{x+1}=\dfrac{x+8}{x-2}+\dfrac{x-8}{x+2}+6\)
d) \(\left(x^2+6x+8\right)\left(x^2+8x+15\right)=24\)
e) \(\left(x^2+x-2\right)\left(x^2+9x+18\right)=28\)
f) \(3\left(-x^2+2x+3\right)^4-26x^2\left(-x^2+2x+3\right)^2-9x^4=0\)
g) \(x^4+6x^3+11x^2+6x+1=0\)
h) \(\left(x-3\right)\left(x-5\right)\left(x-6\right)\left(x-10\right)-24x^2=0\)
i) \(\left(x+2\right)^4+\left(x+8\right)^4=272\)
Giaỉ các phương trình sau:
a) \(\left(x^2+11x+12\right)\left(x^2+9x+20\right)\left(x^2+13x+42\right)=36\left(x^2+11x+30\right)\left(x^2+11x+31\right)\)
b) \(20\left(\frac{x-2}{x+1}\right)^2-5\left(\frac{x+2}{x-1}\right)^2+48\cdot\frac{x^2-4}{x^2-1}=0\)
Tìm x,biết:
a/x+5x^20Leftrightarrow......
b/x+1left(x+1right)^2Leftrightarrow..........
c/x^3+x0Leftrightarrow.......
d/5xleft(x-2right)-left(2-xright)0
e/xleft(2x-1right)+frac{1}{3}-frac{2}{3}x0Leftrightarrow........
g/xleft(x-4right)+left(x-4right)^20Leftrightarrow.....
h/x^2-3x0Leftrightarrow.....
i/4xleft(x+1right)8left(x+1right)Leftrightarrow.....
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Tìm x,biết:
a/\(x+5x^2=0\Leftrightarrow......\)
b/\(x+1=\left(x+1\right)^2\Leftrightarrow..........\)
c/\(x^3+x=0\Leftrightarrow.......\)
d/\(5x\left(x-2\right)-\left(2-x\right)=0\)
e/\(x\left(2x-1\right)+\frac{1}{3}-\frac{2}{3}x=0\Leftrightarrow........\)
g/\(x\left(x-4\right)+\left(x-4\right)^2=0\Leftrightarrow.....\)
h/\(x^2-3x=0\Leftrightarrow.....\)
i/\(4x\left(x+1\right)=8\left(x+1\right)\Leftrightarrow.....\)
Giải phương trình:
1. \(x^2-3x+2+\left|x-1\right|=0\)
2. \(8\left(x+\frac{1}{x}\right)^2+4\left(x^2+\frac{1}{x^2}\right)^2-4\left(x^2+\frac{1}{x^2}\right)\left(x+\frac{1}{x}\right)^2=\left(x+4\right)^2\)
GIÚP MK VS!!!
29 tháng 3 2020 lúc 14:40
Giải phương trình:
a) \(\frac{4x-8+\left(4-2x\right)}{x^2+1}=0\)
b) \(\frac{x^2\left(x-3\right)}{x}=0\)
c) \(\frac{\left(x+2\right)\left(2x-1\right)-x-2}{x^2-x+1}=0\)
3) frac{x-2}{x-5} -frac{5}{x^2-5x}frac{1}{x}
Leftrightarrow frac{x-2}{x-5}-frac{5}{x.left(x-5right)}frac{1}{x}
Leftrightarrowfrac{left(x-2right).left(x+5right)}{x.left(x-5right)}-frac{5}{x.left(x-5right)}frac{1.left(x+5right)}{x.left(x-5right)}
Leftrightarrow x^2+5x-2x-10-51x+5
Leftrightarrow x^2+5x-2x-1x-10-5-5 0
Leftrightarrow x^2+2x-200
Leftrightarrow x^2+2x-10x-200
Leftrightarrow (x^2 + 2x) - (10x + 20) 0
Leftrightarrow x.(x + 2) - 10.(x + 2) 0
Leftrightarrow
4) frac{x-4}{x+7}-f...
Đọc tiếp
3) \(\frac{x-2}{x-5}\) \(-\frac{5}{x^2-5x}=\frac{1}{x}\)
\(\Leftrightarrow\) \(\frac{x-2}{x-5}-\frac{5}{x.\left(x-5\right)}=\frac{1}{x}\)
\(\Leftrightarrow\frac{\left(x-2\right).\left(x+5\right)}{x.\left(x-5\right)}-\frac{5}{x.\left(x-5\right)}=\frac{1.\left(x+5\right)}{x.\left(x-5\right)}\)
\(\Leftrightarrow x^2+5x-2x-10-5=1x+5\)
\(\Leftrightarrow x^2+5x-2x-1x-10-5-5\) = 0
\(\Leftrightarrow\) \(x^2+2x-20=0\)
\(\Leftrightarrow x^2+2x-10x-20=0\)
\(\Leftrightarrow\) (x\(^2\) + 2x) - (10x + 20) = 0
\(\Leftrightarrow\) x.(x + 2) - 10.(x + 2) = 0
\(\Leftrightarrow\)
4) \(\frac{x-4}{x+7}-\frac{1}{x}=\frac{-7}{x^2+7x}\)
\(\Leftrightarrow\frac{x-4}{x+7}-\frac{1}{x}=\frac{-7}{x\left(x+7\right)}\)
\(\Leftrightarrow\frac{\left(x-4\right).\left(x+7\right)}{x.\left(x+7\right)}-\frac{1.\left(x+7\right)}{x.\left(x+7\right)}=\frac{-7}{x.\left(x+7\right)}\)
\(\Leftrightarrow\) \(x^2+7x-4x-28-x-7=-7\)
\(\Leftrightarrow x^2+7x-4x-x-28-7+7=0\)
\(\Leftrightarrow\) x\(^2\) + 2x - 28 = 0
\(\Leftrightarrow\) x\(^2\) + 2x - 14x - 28 = 0
\(\Leftrightarrow\) (x\(^2\) + 2x) - (14x + 28) = 0
\(\Leftrightarrow\) x.(x + 2) - 14.(x + 2) = 0
\(\Leftrightarrow\) (x - 14) = 0 hoặc (x + 2) = 0
\(\Leftrightarrow\) x = 4 (Nhận) hoặc x = -2 (Loại)
5) \(\frac{x+2}{x-2}+\frac{x-2}{x+2}=\frac{8x}{x^2-4}\)
\(\Leftrightarrow\) \(\frac{\left(x+2\right).\left(x+2\right)}{\left(x-2\right).\left(x+2\right)}+\frac{\left(x-2\right).\left(x-2\right)}{\left(x+2\right).\left(x-2\right)}=\frac{8x}{\left(x-2\right).\left(x+2\right)}\)
\(\Leftrightarrow x^2+2x+2x+4+x^2-2x-2x+4=8x\)
\(\Leftrightarrow\) \(x^2+x^2+2x+2x-2x-2x-8x+4+4=0\)
\(\Leftrightarrow2x^2-8x+8=0\)
\(\Leftrightarrow\) 2x\(^2\) - 2x - 8x + 8 = 0
\(\Leftrightarrow\) 2x(x - 1) - 8(x - 1) = 0
\(\Leftrightarrow\) 2x - 8 = 0 hoặc x - 1 = 0
\(\Leftrightarrow\) 2x = 8 hoặc x = 1
\(\Leftrightarrow\) x = 4 (Nhận) hoặc x = 1 (Nhận)
Vậy S = {4; 1}
6) \(\frac{x+1}{x-1}-\frac{x-1}{x+1}=\frac{4}{x^2-1}\)
\(\Leftrightarrow\) \(\frac{\left(x+1\right).\left(x+1\right)}{\left(x-1\right).\left(x+1\right)}-\frac{\left(x-1\right).\left(x-1\right)}{\left(x+1\right).\left(x-1\right)}=\frac{4}{\left(x-1\right).\left(x+1\right)}\)
\(\Leftrightarrow\) x\(^2\) + x + x + 1 - x\(^2\) + x + x - 1 = 4
\(\Leftrightarrow\) 4x - 4 = 0
\(\Leftrightarrow\) 4 (x - 1) =0
\(\Leftrightarrow\) x - 1 = 0 / 4 = 0
\(\Leftrightarrow\) x = 1 (Nhận)
Vậy S = {1}
7) \(\frac{x+1}{x-1}+\frac{-4x}{x^2-1}=\frac{x-1}{x+1}\)
\(\Leftrightarrow\) \(\frac{\left(x+1\right).\left(x+1\right)}{\left(x-1\right).\left(x+1\right)}+\frac{-4x}{\left(x-1\right).\left(x+1\right)}=\frac{\left(x-1\right).\left(x-1\right)}{\left(x+1\right).\left(x+1\right)}\)
\(\Leftrightarrow x^2+x+x+1-4x=x^2-x-x+1\)
\(\Leftrightarrow\) 0
Vậy S ={\(\varnothing\)}
Giải các phương tình sau:
a) left(12x+7right)^2left(3x+2right)left(2x+1right)3
b)8left(x+dfrac{1}{x}right)^2+4left(x^2+dfrac{1}{x^2}right)^2-4left(x^2+dfrac{1}{x^2}right)left(x+dfrac{1}{x}right)^2left(x+4right)^2
c)2xleft(8x-1right)^2left(4x-1right)0
d)x^2-y^2+2x-4y-100 ( x,y là các số nguyên dương )
Đọc tiếp
Giải các phương tình sau:
a) \(\left(12x+7\right)^2\left(3x+2\right)\left(2x+1\right)=3\)
b)\(8\left(x+\dfrac{1}{x}\right)^2+4\left(x^2+\dfrac{1}{x^2}\right)^2-4\left(x^2+\dfrac{1}{x^2}\right)\left(x+\dfrac{1}{x}\right)^2=\left(x+4\right)^2\)
c)\(2x\left(8x-1\right)^2\left(4x-1\right)=0\)
d)\(x^2-y^2+2x-4y-10=0\) ( x,y là các số nguyên dương )
Bài 2: tìm x, biết:
a,left(2x-1right)^2_{ }-1945
b,left(x-3right)^2-xleft(x-7right)12
c,x^2-4+3xleft(x-2right)0
d,x^2-93left(x-3right)
e,3left(3x^2+1right)6-2left(3x+2right)
h,2xleft(x+3right)-4left(x+3right)0
SAVE ME!!!THANK YOU
Đọc tiếp
Bài 2: tìm x, biết:
a,\(\left(2x-1\right)^2_{ }-19=45\)
b,\(\left(x-3\right)^2-x\left(x-7\right)=12\)
c,\(x^2-4+3x\left(x-2\right)=0\)
d,\(x^2-9=3\left(x-3\right)\)
e,\(3\left(3x^2+1\right)=6-2\left(3x+2\right)\)
h,\(2x\left(x+3\right)-4\left(x+3\right)=0\)
SAVE ME!!!THANK YOU