(12x+7)2(3x+2)(2x+1)=3
<=> (144x2+168x+49)(6x2+7x+2)=3
<=>(144x2+168x+49)(144x+168+48)=72
Đặt 144x2+168x+48=t
=> 144x2+168x+49=t+1(*)
Do đó phương trình đã cho là
(t+1)t=72
<=> t2+t-72=0
<=> (t-8)(t+9)=0
<=>\(\left[{}\begin{matrix}t-8=0\\t+9=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}t=8\\t=-9\end{matrix}\right.\)
Bạn tự thay t vào (*) rồi tìm x nha
1. \(\dfrac{5\left(x-1\right)+2}{6}-\dfrac{7x-1}{4}=\dfrac{2\left(2x+1\right)}{7}-5\)
2. \(x-\dfrac{3\left(x+30\right)}{15}-24\dfrac{1}{2}=\dfrac{7x}{10}-\dfrac{2\left(10x+2\right)}{5}\)
3. \(14\dfrac{1}{2}-\dfrac{2\left(x+3\right)}{5}=\dfrac{3x}{2}-\dfrac{2\left(x-7\right)}{3}\)
4. \(\dfrac{x+1}{3}+\dfrac{3\left(2x+1\right)}{4}=\dfrac{2x+3\left(x+1\right)}{6}+\dfrac{7+12x}{12}\)
5. \(\dfrac{3\left(2x-1\right)}{4}-\dfrac{3x+1}{10}+1=\dfrac{2\left(3x+2\right)}{5}\)
6. \(x-\dfrac{3}{17}\left(2x-1\right)=\dfrac{7}{34}\left(1-2x\right)+\dfrac{10x-3}{2}\)
7. \(\dfrac{3\left(x-3\right)}{4}+\dfrac{4x-10,5}{10}=\dfrac{3\left(x+1\right)}{5}+6\)
8. \(\dfrac{2\left(3x+1\right)+1}{4}-5=\dfrac{2\left(3x-1\right)}{5}-\dfrac{3x+2}{10}\)
Giải phương trình
a) \(2x\left(x+5\right)=\left(x+3\right)^2+\left(x-1\right)^2+20\)
b) \(\left(2x-2\right)^3=\left(x+1\right)^2+3\left(x-2\right)\left(x+5\right)\)
c) \(\left(x-1\right)^2+\left(x+3\right)^2=2\left(x-2\right)\left(x+1\right)+38\)
d) \(\left(x+2\right)^3-\left(x-2\right)^3=12x\left(x-2\right)-8\)
Giải phương trình
\(x^4+x^3-12x^2=0\)
\(x^4-3x^3+3x^2-x=0\)
\(6x^4+5x^3-38x^2+5x+6=0\)
\(\left(x^2+5x\right)^2-2\left(x^2+5x\right)-24=0\)
\(\left(x-1\right)^3+\left(2x+3\right)^3=27x^3+8\)
x(x + 1). (x - 1 ). ( x + 2) = 24
giải phương trình
a, \(\dfrac{3}{2x-1}+1=\dfrac{2x-1}{2x+1}\)
b,\(\dfrac{3x-1}{x-1}-\dfrac{2x+5}{x+3}+\dfrac{4}{x^2+2x-3}=1\)
c,\(\dfrac{5}{x^2+x-6}-\dfrac{2}{x^2+4x+3}=\dfrac{-3}{2x-1}\)
d, \(\left(x^2-4\right)\left(2x+3\right)=\left(x^2-4\right)\left(x-1\right)\)
e, \(x^3+x^2+x+1=0\)
giải pt:
\(\left(x^2+3x-4\right)^3+\left(2x^2-5x+3\right)^3=\left(3x^2-2x-1\right)^3\)
Giải phương trình
\(a,\dfrac{x-3}{5}=6-\dfrac{1-2x}{3}\)
\(b,\dfrac{3x-2}{6}-5=\dfrac{3-2\left(x+7\right)}{4}\)
\(c,3\left(x-1\right)+3=5x\)
\(d,\dfrac{x+1}{100}+\dfrac{x+2}{99}=\dfrac{x+3}{98}+\dfrac{x+4}{97}\)
\(e,\dfrac{59-x}{41}+\dfrac{57-x}{43}+\dfrac{55-x}{45}+\dfrac{53-x}{47}=-4\)
\(f,\dfrac{x-90}{10}+\dfrac{x-76}{12}+\dfrac{x-58}{14}+\dfrac{x-36}{16}+\dfrac{x-15}{17}=15\)
Em mới học về pt nên chưa quen lắm mọi người giúp e với ạ !Nguyễn Việt Lâm Quản lý
Giải phương trình:
1. \(\frac{2x+3}{4}-\frac{5x+3}{6}=\frac{3-4x}{12}\)
2. \(\frac{3.\left(2x+1\right)}{4}-1=\frac{15x-1}{10}\)
3. \(\frac{2x-1}{5}-\frac{x-2}{3}=\frac{x+7}{15}\)
4. \(\frac{x+3}{2}-\frac{x-1}{3}=\frac{x+5}{6}+1\)
5. \(\frac{x-4}{5}-\frac{3x-2}{10}-x=\frac{2x-5}{3}-\frac{7x+2}{6}\)
6. \(\frac{\left(x+2\right)\left(x+10\right)}{3}-\frac{\left(x+4\right)\left(x+10\right)}{12}=\frac{\left(x-2\right)\left(x+4\right)}{4}\)
7. \(\frac{\left(x+2\right)^2}{8}-2\left(2x-1\right)=25+\frac{\left(x-2\right)^2}{8}\)
8.\(\frac{7x^2-14x-5}{5}=\frac{\left(2x+1\right)^2}{5}-\frac{\left(x-1\right)^2}{3}\)
9. \(\frac{\left(2x-3\right)\left(2x+3\right)}{8}=\frac{\left(x-4\right)^2}{6}+\frac{\left(x-2\right)^2}{3}\)
10. \(\frac{x+1}{35}+\frac{x+3}{33}=\frac{x+5}{31}+\frac{x+7}{29}\)
