Question

rút gọn P 

Answer 1

Với `x \ne +-2 ; x \ne 1 / 2`. Ta có:

`P = ( 3 / [ 2x + 4 ] + x / [ 2 - x ] + [ 2x^2 + 3 ] / [ x^2 - 4 ] ) : [ 2x - 1 ] / [ 4x - 8 ]`

`P = ( 3 / [ 2 ( x + 2 ) ] - x / [ x  -  2] + [ 2x^2 + 3 ] / [ ( x - 2 ) ( x + 2 ) ] ) . [ 4 ( x - 2 ) ] / [ 2x - 1 ]`

`P = [ 3 ( x - 2 ) - 2x ( x + 2 ) + 2 ( 2x^2 + 3 ) ] / [ 2 ( x - 2 ) ( x + 2 ) ] . [ 4 ( x - 2 ) ] / [ 2x - 1 ]`

`P = [ 3x - 6 - 2x^2 - 4x + 4x^2 + 6 ] / [ x + 2 ] . 1 / [ 2x - 1 ]`

`P = [ 2x^2 - x ] / [ ( x + 2 ) ( 2x - 1 ) ]`

`P = [ x ( 2x - 1 ) ] / [ ( x + 2 ) ( 2x - 1 ) ]`

`P = x / [ x + 2 ]`