Tìm tập xác định của phân thức:
a) 2x2 - x + 5
b) \(\frac{5x^2-8}{2}\)
c) \(\frac{3x^2-2x+1}{2x-4}\)
d) \(\frac{x}{3x^2-3}\)
e) \(\frac{x^2-2x}{x\left(2-x\right)}\)
f) \(\frac{2x}{x^2-5x+6}\)
Những câu hỏi liên quan
14 tháng 2 2020 lúc 16:00
Bài 1: rút gọn phân thứca) frac{14xy^2left(2x-3yright)}{21x^2yleft(2x-3yright)^2}b) frac{8xyleft(3x-1right)^2}{12x^3left(1-3xright)}c) frac{20x^2-45}{left(2x+3right)^2}d) frac{5x^2-10xy}{2left(2y-xright)^3}e) frac{80x^3-125x}{3left(x-3right)-left(x-3right)left(8-4xright)}f) frac{9-left(x+5right)^2}{x^2+4x+4}g) frac{32x-8x^2+2x^3}{x^3+64}h) frac{5x^3+5x}{x^4-1}Bài 2: Quy đồng mẫu thức của các phân thức saua) frac{7x-1}{2x^2+6x};frac{5-3x}{x^2-9}b) frac{x+1}{x-x^2};frac{x+2}{2-4x+2x^2}c) frac{4x^2...
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Bài 1: rút gọn phân thức
a) \(\frac{14xy^2\left(2x-3y\right)}{21x^2y\left(2x-3y\right)^2}\)
b) \(\frac{8xy\left(3x-1\right)^2}{12x^3\left(1-3x\right)}\)
c) \(\frac{20x^2-45}{\left(2x+3\right)^2}\)
d) \(\frac{5x^2-10xy}{2\left(2y-x\right)^3}\)
e) \(\frac{80x^3-125x}{3\left(x-3\right)-\left(x-3\right)\left(8-4x\right)}\)
f) \(\frac{9-\left(x+5\right)^2}{x^2+4x+4}\)
g) \(\frac{32x-8x^2+2x^3}{x^3+64}\)
h) \(\frac{5x^3+5x}{x^4-1}\)
Bài 2: Quy đồng mẫu thức của các phân thức sau
a) \(\frac{7x-1}{2x^2+6x};\frac{5-3x}{x^2-9}\)
b) \(\frac{x+1}{x-x^2};\frac{x+2}{2-4x+2x^2}\)
c) \(\frac{4x^2-3x+5}{x^3-1};\frac{2x}{x^2+x+1};\frac{6}{x-1}\)
d) \(\frac{7}{5x};\frac{4}{x-2y};\frac{x-y}{8y^2-2x^2}\)
Bài 2: \(a,\frac{7x-1}{2x^2+6x}=\frac{7x-1}{2x\left(x+3\right)}=\frac{\left(7x-1\right)\left(x-3\right)}{2x\left(x+3\right)\left(x-3\right)}\)
\(\frac{5-3x}{x^2-9}=\frac{5-3x}{\left(x-3\right)\left(x+3\right)}=\frac{\left(5-3x\right)2x}{2x\left(x-3\right)\left(x+3\right)}\)
\(b,\frac{x+1}{x-x^2}=\frac{x+1}{x\left(1-x\right)}=-\frac{x+1}{x\left(x+1\right)}=-\frac{2\left(x-1\right)\left(x+1\right)}{2x\left(x-1\right)^2}\)
\(\frac{x+2}{2-4x+2x^2}=\frac{x+2}{2\left(x-1\right)^2}=\frac{2x\left(x+2\right)}{2x\left(x-1\right)^2}\)
\(c,\frac{4x^2-3x+5}{x^3-1}=\frac{4x^2-3x+5}{\left(x-1\right)\left(x^2+x+1\right)}\)
\(\frac{2x}{x^2+x+1}=\frac{2x\left(x-1\right)}{\left(x-1\right)\left(x^2+x+1\right)}\)
\(\frac{6}{x-1}=\frac{6\left(x^2+x+1\right)}{\left(x-1\right)\left(x^2+x+1\right)}\)
\(d,\frac{7}{5x}=\frac{7.2\left(2y-x\right)\left(2y+x\right)}{2.5x\left(2y-x\right)\left(2y+x\right)}\)
\(\frac{4}{x-2y}=-\frac{4}{2y-x}=-\frac{4.2.5x\left(2x+x\right)}{2.5x\left(2y-x\right)\left(2y+x\right)}\)
\(\frac{x-y}{8y^2-2x^2}=\frac{x-y}{2\left(4y^2-x^2\right)}=\frac{x-y}{2\left(2y-x\right)\left(2y+x\right)}=\frac{5x\left(x-y\right)}{2.5x.\left(2y-x\right)\left(2y+x\right)}\)
giải các hệ BPT sau:
a) left{{}begin{matrix}5x-24x+55x-4 x+2end{matrix}right.
b) left{{}begin{matrix}2x+13x+45x+3ge8x-9end{matrix}right.
c) left{{}begin{matrix}frac{5x+2}{3}ge4-xfrac{6-5x}{13} 3x+1end{matrix}right.
d) left{{}begin{matrix}frac{4x-5}{7} x+3frac{3x+8}{4}2x-5end{matrix}right.
e) left{{}begin{matrix}6x+frac{5}{7} 4x+7frac{8x+3}{2} 2x+5end{matrix}right.
f) left{{}begin{matrix}15x-22x+frac{1}{3}2left(x-4right) frac{3x-14}{2}end{matrix}right.
g) left{{}begin{matrix}x-1le2x-33x x+...
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giải các hệ BPT sau:
a) \(\left\{{}\begin{matrix}5x-2>4x+5\\5x-4< x+2\end{matrix}\right.\)
b) \(\left\{{}\begin{matrix}2x+1>3x+4\\5x+3\ge8x-9\end{matrix}\right.\)
c) \(\left\{{}\begin{matrix}\frac{5x+2}{3}\ge4-x\\\frac{6-5x}{13}< 3x+1\end{matrix}\right.\)
d) \(\left\{{}\begin{matrix}\frac{4x-5}{7}< x+3\\\frac{3x+8}{4}>2x-5\end{matrix}\right.\)
e) \(\left\{{}\begin{matrix}6x+\frac{5}{7}< 4x+7\\\frac{8x+3}{2}< 2x+5\end{matrix}\right.\)
f) \(\left\{{}\begin{matrix}15x-2>2x+\frac{1}{3}\\2\left(x-4\right)< \frac{3x-14}{2}\end{matrix}\right.\)
g) \(\left\{{}\begin{matrix}x-1\le2x-3\\3x< x+5\\5-3x\le2x-6\end{matrix}\right.\)
h) \(\left\{{}\begin{matrix}2x+\frac{3}{5}>\frac{3\left(2x-7\right)}{3}\\x-\frac{1}{2}< \frac{5\left(3x-1\right)}{2}\end{matrix}\right.\)
j) \(\left\{{}\begin{matrix}\frac{3x+1}{2}-\frac{3-x}{3}\le\frac{x+1}{4}-\frac{2x-1}{3}\\3-\frac{2x+1}{5}>x+\frac{4}{3}\end{matrix}\right.\)
https://i.imgur.com/NOxfqjV.jpg
https://i.imgur.com/awOKwJi.jpg
https://i.imgur.com/a0ApmAE.jpg
Câu 3: Giải các phương trình sau bằng cách đưa về dạng ax+b0
1. a, frac{5x-2}{3}frac{5-3x}{2}; b, frac{10x+3}{12}1+frac{6+8x}{9}
c, 2left(x+frac{3}{5}right)5-left(frac{13}{5}+xright); d, frac{7}{8}x-5left(x-9right)frac{20x+1,5}{6}
e, frac{7x-1}{6}+2xfrac{16-x}{5}; f, 4 (0,5-1,5x)frac{5x-6}{3}
g, frac{3x+2}{2}-frac{3x+1}{6}frac{5}{3}+2x; h, frac{x+4}{5}.x+4frac{x}{3}-frac{x-2}{2}
i, frac{4x+3}{5}-frac{6x-2}{7}fr...
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Câu 3: Giải các phương trình sau bằng cách đưa về dạng ax+b=0
1. a, \(\frac{5x-2}{3}=\frac{5-3x}{2}\); b, \(\frac{10x+3}{12}=1+\frac{6+8x}{9}\)
c, \(2\left(x+\frac{3}{5}\right)=5-\left(\frac{13}{5}+x\right)\); d, \(\frac{7}{8}x-5\left(x-9\right)=\frac{20x+1,5}{6}\)
e, \(\frac{7x-1}{6}+2x=\frac{16-x}{5}\); f, 4 (0,5-1,5x)=\(\frac{5x-6}{3}\)
g, \(\frac{3x+2}{2}-\frac{3x+1}{6}=\frac{5}{3}+2x\); h, \(\frac{x+4}{5}.x+4=\frac{x}{3}-\frac{x-2}{2}\)
i, \(\frac{4x+3}{5}-\frac{6x-2}{7}=\frac{5x+4}{3}+3\); k, \(\frac{5x+2}{6}-\frac{8x-1}{3}=\frac{4x+2}{5}-5\)
m, \(\frac{2x-1}{5}-\frac{x-2}{3}=\frac{x+7}{15}\); n, \(\frac{1}{4}\left(x+3\right)=3-\frac{1}{2}\left(x+1\right).\frac{1}{3}\left(x+2\right)\)
p, \(\frac{x}{3}-\frac{2x+1}{6}=\frac{x}{6}-x\); q, \(\frac{2+x}{5}-0,5x=\frac{1-2x}{4}+0,25\)
r, \(\frac{3x-11}{11}-\frac{x}{3}=\frac{3x-5}{7}-\frac{5x-3}{9}\); s, \(\frac{9x-0,7}{4}-\frac{5x-1,5}{7}=\frac{7x-1,1}{6}-\frac{5\left(0,4-2x\right)}{6}\)
t, \(\frac{2x-8}{6}.\frac{3x+1}{4}=\frac{9x-2}{8}+\frac{3x-1}{12}\); u, \(\frac{x+5}{4}-\frac{2x-3}{3}=\frac{6x-1}{3}+\frac{2x-1}{12}\)
v, \(\frac{5x-1}{10}+\frac{2x+3}{6}=\frac{x-8}{15}-\frac{x}{30}\); w, \(\frac{2x-\frac{4-3x}{5}}{15}=\frac{7x\frac{x-3}{2}}{5}-x+1\)
Đây là những bài cơ bản mà bạn!
\(\frac{5x-2}{3}=\frac{5-3x}{2}\)
\(< =>\frac{\left(5x-2\right).2}{6}=\frac{\left(5-3x\right).3}{6}\)
\(< =>\left(5x-2\right).2=\left(5-3x\right).3\)
\(< =>10x-4=15-9x\)
\(< =>10x+9x=15+4\)
\(< =>19x=19< =>x=1\)
\(\frac{10x+3}{12}=1+\frac{6+8x}{9}\)
\(< =>\frac{\left(10x+3\right).3}{36}=\frac{36}{36}+\frac{\left(6+8x\right).4}{36}\)
\(< =>\left(10x+3\right).3=36+\left(6+8x\right).4\)
\(< =>30x+9=36+24+32x\)
\(< =>32x-30x=9-36-24\)
\(< =>2x=9-60=-51< =>x=-\frac{51}{2}\)
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Bài 1: Giải phương trình:
a) 11 - (2x + 3) 3 (x - 4)
b) 5(2x - 3) - 4(5x - 7) 19 - 2x
c) frac{x}{3}-frac{2x+1}{2}frac{x}{6}-x
d) frac{5x+2}{6}-frac{8x-1}{3}frac{4x+2}{5}-5
e) frac{2left(1-3xright)}{5}-frac{2+3x}{10}7-frac{3left(2x+1right)}{4}
f) frac{3x+2}{2}-frac{3x+1}{6}2x+frac{5}{3}
Bài 2: Giải phương trình sau bằng cách đưa về phương trình tích:
a) (x + 1)(x + 2)(x + 3) 0
b) (x + 1)2 - 16 0
c) (2x - 1)2 (x + 3)2
d) (2x + 1)(3x - 2) (5x - 8)(2x + 1)
e) x2 - 5x + 6 0
f) 2x3...
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Bài 1: Giải phương trình:
a) 11 - (2x + 3) = 3 (x - 4)
b) 5(2x - 3) - 4(5x - 7) = 19 - 2x
c) \(\frac{x}{3}-\frac{2x+1}{2}=\frac{x}{6}-x\)
d) \(\frac{5x+2}{6}-\frac{8x-1}{3}=\frac{4x+2}{5}-5\)
e) \(\frac{2\left(1-3x\right)}{5}-\frac{2+3x}{10}=7-\frac{3\left(2x+1\right)}{4}\)
f) \(\frac{3x+2}{2}-\frac{3x+1}{6}=2x+\frac{5}{3}\)
Bài 2: Giải phương trình sau bằng cách đưa về phương trình tích:
a) (x + 1)(x + 2)(x + 3) = 0
b) (x + 1)2 - 16 = 0
c) (2x - 1)2 = (x + 3)2
d) (2x + 1)(3x - 2) = (5x - 8)(2x + 1)
e) x2 - 5x + 6 = 0
f) 2x3 + 5x2 - 3x = 0
Các thầy cô giáo và bạn bè giúp em với ạ. Em cảm ơn !
Đừng bơ em, em tội nghiệp T^T ...
Bạn đưa quá nhiều bài 1 lúc nên người ta giải được cũng chẳng ai muốn giải đâu, vì nhìn vào đã thấy ngộp rồi. Kinh nghiệm là muốn được giải quyết nhanh thì chỉ đăng 2-3 bài 1 lúc thôi
Bài 1:
a/ \(11-\left(2x+3\right)=3\left(x-4\right)\)
\(\Leftrightarrow11-2x-3=3x-12\)
\(\Leftrightarrow5x=20\)
\(\Rightarrow x=4\)
b/ \(5\left(2x-3\right)-4\left(5x-7\right)=19-2x\)
\(\Leftrightarrow10x-15-20x+28=19-2x\)
\(\Leftrightarrow8x=-6\)
\(\Rightarrow x=-\frac{3}{4}\)
c/
\(\frac{x}{3}-\frac{2x+1}{2}=\frac{x}{6}-x\)
\(\Leftrightarrow2x-3\left(2x+1\right)=x-6x\)
\(\Leftrightarrow x=3\)
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d/
\(\frac{5x+2}{6}-\frac{8x-1}{3}=\frac{4x+2}{5}-5\)
\(\Leftrightarrow5\left(5x+2\right)-10\left(8x-1\right)=6\left(4x+2\right)-150\)
\(\Leftrightarrow79x=158\)
\(\Rightarrow x=2\)
e/
\(\frac{2-6x}{5}-\frac{2+3x}{10}=7-\frac{6x+3}{4}\)
\(\Leftrightarrow4\left(2-6x\right)-2\left(2+3x\right)=140-5\left(6x+3\right)\)
\(\Leftrightarrow0=-121\) (vô lý)
Vậy pt vô nghiệm
f/
\(\frac{3x+2}{2}-\frac{3x+1}{6}=2x+\frac{5}{3}\)
\(\Leftrightarrow3\left(3x+2\right)-\left(3x+1\right)=12x+10\)
\(\Leftrightarrow6x=-5\)
\(\Rightarrow x=-\frac{5}{6}\)
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Bài 2:
a/ \(\left(x+1\right)\left(x+2\right)\left(x+3\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x+1=0\\x+2=0\\x+3=0\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=-1\\x=-2\\x=-3\end{matrix}\right.\)
b/
\(\left(x+1\right)^2-4^2=0\)
\(\Leftrightarrow\left(x+1-4\right)\left(x+1+4\right)=0\)
\(\Leftrightarrow\left(x-3\right)\left(x+5\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-3=0\\x+5=0\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=3\\x=-5\end{matrix}\right.\)
c/
\(\left(2x-1\right)^2=\left(x+3\right)^2\)
\(\Leftrightarrow\left(2x-1\right)^2-\left(x+3\right)^2=0\)
\(\Leftrightarrow\left(2x-1-x-3\right)\left(2x-1+x+3\right)=0\)
\(\Leftrightarrow\left(x-4\right)\left(3x+2\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-4=0\\3x+2=0\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=4\\x=-\frac{2}{3}\end{matrix}\right.\)
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Giải các phương trình sau:
a, 2x - 3 = 5x + 6
b, ( 2x + 1 ).( 3x - 2 ) = ( 5x - 8 ).( 2x + 1 )
c, \(\frac{2x+1}{3}-\frac{7x+5}{15}=\frac{2x-2}{5}\)
d,\(\frac{3x}{x-2}-\frac{x}{x-5}=\frac{3x}{\left(x-2\right).\left(5-x\right)}\)
e, ( x2 + 2x )2 + 9x2 + 18x + 20 = 0
Giúp ik a~
a , 2x -3 = 5x + 6
2x -5x=6+3
-3x = 9
x =9 :(-3)
x= -3
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a) 2x-5x=3+6
-3x=9
x=-3
vậy........
b)(2x+1).(3x-2)-(5x-8).(2x+1)=0
(2x+1).(3x-2-2x-1)=0
(2x-1).(x-3)=0
==>x=1/2 ; x=3
c)(2x+1).5-(7x+5)=(2x-2).3
10x+5-7x-5=6x-6
3x=6x-6
3x-6x=6
-3x=6
x=-2
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a) 2x - 3 = 5x + 6
<=> -3x = 9
<=> x = -3
b) (2x + 1).(3x - 2) = (5x - 8).(2x + 1)
<=> 6x2 - 4x + 3x - 2 = 10x2 + 5x - 16x -8
<=> -4x2 - 10x + 6 = 0
<=> \(\orbr{\begin{cases}x=\frac{1}{2}\\x=-3\end{cases}}\)
c) \(\frac{2\text{x}+1}{3}-\frac{7\text{x}+5}{15}=\frac{2\text{x}-2}{5}\)
<=> \(\frac{5.\left(2\text{x}+1\right)}{5.3}-\frac{7\text{x}+5}{15}=\frac{3.\left(2\text{x}-2\right)}{3.5}\)
<=> 10x + 5 - 7x + 5 - 6x + 6 = 0
<=> -3x + 16 = 0
<=> -3x = -16
<=> x = \(\frac{16}{3}\)
d) \(\frac{3x}{x-2}-\frac{x}{x-5}=\frac{3\text{x}}{\left(x-2\right).\left(5-x\right)}\)
<=> \(\frac{3\text{x}\left(x-5\right)-x\left(x-2\right)}{\left(x-2\right).\left(5-x\right)}=\frac{3\text{x}}{\left(x-2\right).\left(5-x\right)}\)
<=> 3x2 - 15x - x2 + 2x - 3x = 0
*Câu e dễ quá, bạn tự làm nhé :v*
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1)2x(25x-4)-(5x-2)(5x+1)8 / 5)2left(x-2right)-3left(3x-1right)left(x-3right)
2)x(4x-3)-(2x-2)(2x-1)5 / 6)frac{2}{x+1}-frac{1}{x-2}frac{3x-11}{left(x+1right)left(x-2right)}
3)frac{5}{2x+3}+frac{3}{9-x^2}frac{8}{7left(x3right)} / 7)frac{5x-2}{6}+frac{3-4x}{2}2-frac{x+7}{3}
4)frac{2}{3left(x-2right)}+frac{5}{12-3x^2}frac{3}{4left(x+2right)} /...
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1)2x(25x-4)-(5x-2)(5x+1)=8 / 5)\(2\left(x-2\right)-3\left(3x-1\right)=\left(x-3\right)\)
2)x(4x-3)-(2x-2)(2x-1)=5 / 6)\(\frac{2}{x+1}-\frac{1}{x-2}=\frac{3x-11}{\left(x+1\right)\left(x-2\right)}\)
3)\(\frac{5}{2x+3}+\frac{3}{9-x^2}=\frac{8}{7\left(x=3\right)}\) / 7)\(\frac{5x-2}{6}+\frac{3-4x}{2}=2-\frac{x+7}{3}\)
4)\(\frac{2}{3\left(x-2\right)}+\frac{5}{12-3x^2}=\frac{3}{4\left(x+2\right)}\) / 8)\(\frac{2}{x+1}-\frac{1}{x-2}=\frac{3x-11}{\left(x+1\right)\left(x-2\right)}\)
Đây là lớp 8 nha các b giúp mk với
Do mk viết nhầm
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1,Tìm x:
a,3x-2=0
b,2x-1=0
c,5.(4+2x)=8+5x
d,\(\frac{1}{2}+\frac{3}{4}x=6-\frac{4}{5}x\)
e,3+2x=4-8x
f,\(5+\frac{1}{2}.\left(x+5\right)=3\)
a) 3x - 2 = 0 => 3x = 2 => x = 2/3
b) 2x - 1 = 0 => 2x = 1 => x = 1/2
c) 5 ( 4+2x) = 8+5x
<=> 20 + 10x = 8 + 5x
<=> 10x - 5x = 8 - 20
<=> 5x = -12
x = -12/5
d) \(\frac{1}{2}+\frac{3}{4}x=6-\frac{4}{5}x\)
\(\frac{3}{4}x+\frac{4}{5}x=6-\frac{1}{2}\)
\(\frac{31}{20}x=\frac{11}{2}\)
\(x=\frac{11}{2}:\frac{31}{20}=\frac{110}{31}\)
e) 3 + 2x = 4 - 8x
<=> 2x + 8x = 4 - 3
10 x = 1
x = 1/10
f \(5+\frac{1}{2}\left(x+5\right)=3\)
\(\frac{1}{2}\left(x+5\right)=3-5=-2\)
\(x+5=-2:\frac{1}{2}=-4\)
\(x=-4-5=1\)
Vậy ......
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Giải các phương trình sau :a,6x^2-5x+32x-3xleft(3-2xright)b,frac{2left(x-4right)}{4}-frac{3+2x}{10}x+frac{1-x}{5}c,frac{2x}{3}+frac{3x-5}{4}frac{3left(2x-1right)}{2}-frac{7}{6}d,frac{6x+5}{2}-frac{10x+3}{4}2x+frac{2x+1}{2}e,left(x-4right)left(x+4right)-2left(3x-2right)left(x-4right)^2
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Giải các phương trình sau :
\(a,6x^2-5x+3=2x-3x\left(3-2x\right)\)
\(b,\frac{2\left(x-4\right)}{4}-\frac{3+2x}{10}=x+\frac{1-x}{5}\)
\(c,\frac{2x}{3}+\frac{3x-5}{4}=\frac{3\left(2x-1\right)}{2}-\frac{7}{6}\)
\(d,\frac{6x+5}{2}-\frac{10x+3}{4}=2x+\frac{2x+1}{2}\)
\(e,\left(x-4\right)\left(x+4\right)-2\left(3x-2\right)=\left(x-4\right)^2\)
a) <=> \(6x^2-5x+3-2x+3x\left(3-2x\right)=0\)
<=> \(6x^2-5x+3-2x+9x-6x^2=0\)
<=> \(2x+3=0\)
<=> \(x=\frac{-3}{2}\)
b) <=> \(10\left(x-4\right)-2\left(3+2x\right)=20x+4\left(1-x\right)\)
<=> \(10x-40-6-4x=20x+4-4x\)
<=> \(6x-46-16x-4=0\)
<=> \(-10x-50=0\)
<=> \(-10\left(x+5\right)=0\)
<=> \(x+5=0\)
<=> \(x=-5\)
c) <=> \(8x+3\left(3x-5\right)=18\left(2x-1\right)-14\)
<=> \(8x+9x-15=36x-18-14\)
<=> \(8x+9x-36x=+15-18-14\)
<=> \(-19x=-14\)
<=> \(x=\frac{14}{19}\)
d) <=>\(2\left(6x+5\right)-10x-3=8x+2\left(2x+1\right)\)
<=> \(12x+10-10x-3=8x+4x+2\)
<=> \(2x-7=12x+2\)
<=> \(2x-12x=7+2\)
<=> \(-10x=9\)
<=> \(x=\frac{-9}{10}\)
e) <=> \(x^2-16-6x+4=\left(x-4\right)^2\)
<=> \(x^2-6x-12-\left(x-4^2\right)=0\)
<=> \(x^2-6x-12-\left(x^2-8x+16\right)=0\)
<=> \(x^2-6x-12-x^2+8x-16=0\)
<=> \(2x-28=0\)
<=> \(2\left(x-14\right)=0\)
<=> x-14=0
<=> x=14
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Luffy , cậu sai câu c nhé , kia là -17 ạ => x=17/19
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Bài 2. Giải các phương trình sau
a, frac{x}{3}-frac{5x}{6}-frac{15x}{12}frac{x}{4}-5
b, frac{8x-3}{4}-frac{3x-2}{2}frac{2x-1}{2}+frac{x+3}{4}
c, frac{x-1}{2}-frac{x+1}{15}-frac{2x-13}{6}0
d,frac{3left(3-xright)}{8}+frac{2left(5-xright)}{3}frac{1-x}{2}-2
e, frac{3left(5x-2right)}{4}-2frac{7x}{3}-5left(x-7right)
f, frac{x+5}{2}+frac{3-2x}{4}x-frac{7+x}{6}
g, frac{x-3}{11}+frac{x+1}{3}frac{x+7}{9}-1
h, frac{3x-0,4}{2}+frac{1,5-2x}{3}frac{x+0,5}{5}
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Bài 2. Giải các phương trình sau
a, \(\frac{x}{3}-\frac{5x}{6}-\frac{15x}{12}=\frac{x}{4}-5\)
b, \(\frac{8x-3}{4}-\frac{3x-2}{2}=\frac{2x-1}{2}+\frac{x+3}{4}\)
c, \(\frac{x-1}{2}-\frac{x+1}{15}-\frac{2x-13}{6}=0\)
d,\(\frac{3\left(3-x\right)}{8}+\frac{2\left(5-x\right)}{3}=\frac{1-x}{2}-2\)
e, \(\frac{3\left(5x-2\right)}{4}-2=\frac{7x}{3}-5\left(x-7\right)\)
f, \(\frac{x+5}{2}+\frac{3-2x}{4}=x-\frac{7+x}{6}\)
g, \(\frac{x-3}{11}+\frac{x+1}{3}=\frac{x+7}{9}-1\)
h, \(\frac{3x-0,4}{2}+\frac{1,5-2x}{3}=\frac{x+0,5}{5}\)
a)
\(\frac{x}{3}-\frac{5x}{6}-\frac{15x}{12}=\frac{x}{4}-5\)
\(\Leftrightarrow\frac{4x-10x-15x}{12}=\frac{3x-60}{12}\)
\(\Leftrightarrow\frac{-10x-11}{12}=\frac{3x-60}{12}\)
\(\Leftrightarrow\frac{-10x-11-3x+60}{12}=0\)
\(\Leftrightarrow\frac{49-13x}{12}=0\)
\(\Rightarrow49-13x=0\)
\(\Rightarrow x=\frac{-49}{13}\)
b)
\(\frac{8x-3}{4}-\frac{3x-2}{2}=\frac{2x-1}{2}+\frac{x+3}{4}\)
\(\Leftrightarrow\frac{8x-3-6x+4}{4}=\frac{4x-2+x+3}{4}\)
\(\Leftrightarrow\frac{2x+1}{4}=\frac{5x+1}{4}\)
\(\Leftrightarrow\frac{2x+1-5x-1}{4}=0\)
\(\Leftrightarrow\frac{-3x}{4}=0\)
\(\Rightarrow-3x=0\)
\(\Rightarrow x=0\)
e)
\(\frac{3\cdot\left(5x-2\right)}{4}-2=\frac{7x}{3}-5\cdot\left(x-7\right)\)
\(\Leftrightarrow\frac{45x-18-24-28x+60x-420}{12}=0\)
\(\Leftrightarrow\frac{77x-462}{12}=0\)
\(\Rightarrow77x-462=0\)
\(\Rightarrow x=\frac{462}{77}=6\)
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