Răspuns :
[ x ·( 2x -1) + 2 ·( 2x + 1) - 3x -1 ] / ( 4x² -1) =
= [ 2x² -x + 4x + 2 -3x -1 ] / ( 4x² -1) =
= [ 2x² + 1 ] / ( 2x -1 ) ·( 2x +1)
= [ 2x² -x + 4x + 2 -3x -1 ] / ( 4x² -1) =
= [ 2x² + 1 ] / ( 2x -1 ) ·( 2x +1)
[tex]\displaystyle \frac{x}{2x+1} + \frac{2}{2x-1} - \frac{3x+1}{4x^2-1} = \frac{x}{2x+1} + \frac{2}{2x-1}- \frac{3x+1}{(2x-1)(2x+1)} = \\ \\ = \frac{x(2x-1)+2(2x+1)-3x-1}{(2x-1)(2x+1)} = \frac{2x^2-x+4x+2-3x-1}{(2x-1)(2x+1)} = \\ \\ = \frac{2x^2+1}{(2x-1)(2x+1)} [/tex]