⇔1/a+b−x − 1/x = 1/a + 1/b⇔1/a+b−x − 1/x = 1/a + 1/b
⇔2x−(a+b) / (a+b−x)x = 1/a + 1/b
<=>(a+b)(a+b−x)x=ab(2x−a−b)
<=>(a+b)2x−x2(a+b)=2abx−(a+b)ab
<=>x2(a+b)−(a2+b2)x−ab(a+b)=0
<=>(a+b)(a+b−x)x=ab(2x−a−b)
<=>(a+b)2x−x2(a+b)=2abx−(a+b)ab
<=>x2(a+b)−(a2+b2)x−ab(a+b)=0
Giải các pt với tham số là a,b,c
a , \(\dfrac{x-a}{3}=\dfrac{x+3}{a}-2\) e, \(3x+\dfrac{x}{a}-\dfrac{3a}{a+1}=\dfrac{4ax}{\left(a+1\right)^2}+\dfrac{\left(2a+1\right)x}{a\left(a+1\right)^2}-\dfrac{3a^2}{\left(a+1\right)^3}\)
b, \(\dfrac{x-a}{a+1}+\dfrac{x-1}{a-1}=\dfrac{2a}{1-a^2}\)
c, \(\dfrac{x+a-1}{a+2}+\dfrac{x-a}{a-2}+\dfrac{x-a}{4-a^2}\)
d, \(\dfrac{x-a}{b+c}+\dfrac{x-b}{c+a}+\dfrac{x-c}{a+b}=3\)
giải pt
a)\(\dfrac{1}{x^2-3x+2}+\dfrac{1}{x^2-5x+6}-\dfrac{2}{x^2-4x+3}\)
b)\(\dfrac{1}{x^2+9x+20}+\dfrac{1}{x^2+11x+30}+\dfrac{1}{x^2+13x+42}=\dfrac{1}{18}\)
Giải pt: \(\dfrac{3}{5x-1}+\dfrac{2}{3-5x}=\dfrac{4}{\left(1-5x\right)\left(x-3\right)}\)
\(\dfrac{5+96}{x^2-16}=\dfrac{2x—1}{x+4}-\dfrac{3x-1}{4-x}\)
Bt: Giải các pt sau:
a, \(\dfrac{x+3}{x+1}\) + \(\dfrac{x-2}{x}\)=\(\dfrac{2\left(x^2+x-1\right)}{x\left(x+1\right)}\)
b, \(\dfrac{2}{x-2}-\dfrac{x}{x+3}=\dfrac{5x}{\left(x-2\right)\left(x+3\right)}-1\)
c, \(\dfrac{1}{x^2+x+1}-\dfrac{1}{x^2-x+1}=\dfrac{1-2x}{x^4+x^2+1}\)
d, \(\dfrac{3x-1}{x-1}-\dfrac{2x+5}{x+3}+\dfrac{4}{x^2+2x-3}=1\)
e, \(\left(x+1\right)\left(x+2\right)\left(x+4\right)\left(x+5\right)=40\)
Giải các phương trình sau:
a) \(\dfrac{1}{x^2-7x+12}+\dfrac{1}{x^2-11x+28}+\dfrac{1}{x^2-19x+84}=\dfrac{1}{4}\)
b) \(\dfrac{1}{x^2+x}+\dfrac{1}{x^2+3x+2}+\dfrac{1}{x^2+5x+6}+\dfrac{1}{x^2+7x+12}=\dfrac{1}{2}\)
Bài 2:giải các pt chứa ẩn ở mẫu sau:
a)\(\dfrac{x+1}{x-1}-\dfrac{x-1}{x+1}=\dfrac{16}{x^2-1}\)
b)\(\dfrac{12}{x^2-4}-\dfrac{x+1}{x-2}+\dfrac{x+7}{x+2}=0\)
c)\(\dfrac{12}{8+x^3}=1+\dfrac{1}{x+2}\)
d)\(\dfrac{x+25}{2x^2-50}-\dfrac{x+5}{x^2-5x}=\dfrac{5-x}{2x^2+10x}\)
giúp mình với ạ
Bài 1: giải các PT:
a, \(\dfrac{1}{2}\left(x+1\right)+\dfrac{1}{4}\left(x+3\right)=3-\dfrac{1}{3}\left(x+2\right)\)
b, \(\dfrac{x+2}{98}+\dfrac{x+4}{96}=\dfrac{x+6}{94}+\dfrac{x+8}{92}\)
c, \(\dfrac{x-12}{77}+\dfrac{x-11}{78}=\dfrac{x-74}{15}+\dfrac{x-73}{16}\)
d, \(\dfrac{x+\dfrac{2\left(3-x\right)}{5}}{14}-\dfrac{5x-4\left(x-1\right)}{24}=\dfrac{7x+2+\dfrac{9-3x}{5}}{12}+\dfrac{2}{3}\)
\(e,\dfrac{x-\dfrac{3}{2014}+\dfrac{x-2}{2015}=\dfrac{x-2015}{2}+\dfrac{x-2014}{3}}{ }\)
Giải các pt sau:
a) \(\dfrac{1}{x-1}-\dfrac{7}{x+2}=\dfrac{3}{x^2+x-2}\)
b) \(\dfrac{x^2+2x+1}{x^2+2x+2}+\dfrac{x^2+2x+2}{x^2+2x+3}=\dfrac{7}{6}\)
Giải các phương trình sau:
a) \(\dfrac{1}{x-1}+\dfrac{2}{x^2+x+1}=\dfrac{3x^2}{x^3-1}\)
b) \(\dfrac{4}{x^2-1}+1=\dfrac{1}{x-2}\)
c) \(\dfrac{x}{x-1}=\dfrac{2x}{x^2-1}\)
d) \(\dfrac{x+5}{x-1}=\dfrac{x+1}{x-4}=\dfrac{8}{\left(x-1\right)\left(x-3\right)}\)
