Question

Answer 1

a, \(x\left(4x-1\right)-8\left(4x-1\right)=0\)

\(\Leftrightarrow\left(x-4\right)\left(4x-1\right)=0\Leftrightarrow x=4;x=\dfrac{1}{4}\)

b, \(9x^2-5x-9x+5=0\)

\(\Leftrightarrow9x\left(x-1\right)-5\left(x-1\right)=0\Leftrightarrow\left(9x-5\right)\left(x-1\right)=0\Leftrightarrow x=\dfrac{5}{9};x=1\)

c, đk : x khác -1 ; 2 

\(\Rightarrow2x-4-x-1=3x-11\Leftrightarrow-2x=-6\Leftrightarrow x=3\left(tm\right)\)

d, đk : x khác -1 ; -2 

\(1+x\left(x+1\right)=x^2+3x+2\Leftrightarrow x^2+x+1=x^2+3x+2\Leftrightarrow2x=-1\Leftrightarrow x=-\dfrac{1}{2}\left(tm\right)\)