1) 6а/( а^2 - b^2 ) - 2/( a + b ) + 3/( b - a ) = ( 6a - 2( a - b ) - 3( a + b ) / ( a^2 - b^2 ) = ( 6a - 2a + 2b - 3a - 3b ) / ( a^2 - b^2 ) = ( a - b ) / ( a^2 - b^2 ) = 1 / ( a + b )
2) 1 / ( a + b ) : 1 / ( 4a + 4b ) = 1 /( а + b ) • ( 4( a + b )) = 4
Ответ 4