giải các phương trình sau A/ \(3\left(x-1\right).\left(2x-1\right)=5\left(x+8\right).\left(x-1\right)\)B/ \(9x^2-1=\left(3x+1\right).\left(4x+1\right)\)C/ \(x^3-5x^2+6x=0\)D/ \(\frac{2x+1}{2x+1}-\frac{2x-1}{2x-1}=\frac{8}{4x^2-1}\)E/ ...
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giải các phương trình sau
A/ \(3\left(x-1\right).\left(2x-1\right)=5\left(x+8\right).\left(x-1\right)\)
B/ \(9x^2-1=\left(3x+1\right).\left(4x+1\right)\)
C/ \(x^3-5x^2+6x=0\)
D/ \(\frac{2x+1}{2x+1}-\frac{2x-1}{2x-1}=\frac{8}{4x^2-1}\)
E/ \(\frac{6}{x^2-1}+5=\frac{8x-1}{4x+4}-\frac{12x-1}{4-4x}\)
giúp mình bài ni với : x^2-y^2+2x+1
a) \(3\left(x-1\right)\left(2x-1\right)=5\left(x+8\right)\left(x-1\right)\)
\(\Leftrightarrow6x^2-3x-6x+3=5x^2-5x+40x-40\)
\(\Leftrightarrow6x^2-9x+3=5x^2+35x-40\)
\(\Leftrightarrow6x^2-9x+3-5x^2-35x+40=0\)
\(\Leftrightarrow x^2-44x+43=0\)
\(\Leftrightarrow\left(x-43\right)\left(x-1\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x-43=0\\x-1=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=43\\x=0\end{cases}}\)
b) \(9x^2-1=\left(3x+1\right)\left(4x+1\right)\)
\(\Leftrightarrow9x^2-1=12x^2+3x+4x+1\)
\(\Leftrightarrow9x^2-1=12x^2+7x+1\)
\(\Leftrightarrow9x^2-1-12x^2-7x-1=0\)
\(\Leftrightarrow-3x^2-2-7x=0\)
\(\Leftrightarrow3x^2+7x+2=0\)
\(\Leftrightarrow3x^2+6x+x+2=0\)
\(\Leftrightarrow3x\left(x+2\right)+\left(x+2\right)=0\)
\(\Leftrightarrow\left(x+2\right)\left(3x+1\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x+2=0\\3x+1=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=-2\\x=-\frac{1}{3}\end{cases}}\)