1)
2а
=(----- - 4а^2/(2а+б)^2)÷
2а+б
÷(2а/(2а-б)(2а+б) -1/(2а-б))=
2а(2а+б)-4а^2
=-------------------- ÷
(2а+б)^2
2а -1(2а+б)
÷----------------=
(2а-б)(2а+б)
4а^2+2аб-4а^2
=----------------- ÷
(2а+б)^2
2а-2а-б
÷-----------------=
(2а-б)(2а+б)
=2аб/(2а+б)^2 ÷(-б)/(2а-б)(2а+б)=
2аб(2а-б)(2а+б)
=---------------------= - 2а(2а-б)/(2а+б)
(2а+б)^2×(-б)
2)
=(1/(х+1) -3/(х+1)(х^2-х+1) +3/(х^2-х+1))×
×(х- (2х-1)/(х+1))=
х^2-х+1-3+3(х+1)
=------------------------- ×
(х+1)(х^2-х+1)
х(х+1)-(2х-1)
×---------------=
х+1
х^2-х-2+3х+3
=------------------ ×
(х+1)(х^2-х+1)
х^2+х-2х+1
×----------------=
х+1
х^2+2х+1
=-------------------- ×
(х+1)(х^2-х+1)
х^2-х+1
×--------------=
х+1
(х+1)^2 ×(х^2-х+1)
=------------------------------=1
(х+1)(х^2-х+1)×(х+1)