Объяснение:
б ) 12x²+ 18y + 10x³+ 15xy = ( 12x²+ 18y ) + (10x³+ 15xy ) = 6( 2x²+ 3y ) +
+ 5x( 2x²+ 3y ) = ( 2x²+ 3y )( 5x + 6 ) ;
в ) a²b + a + ab² + b + 2ab + 2 = ( a²b + a ) + ( ab² + b ) + ( 2ab + 2 ) =
= a( ab + 1 ) + b( ab + 1 ) + 2( ab + 1 ) = ( ab + 1 )( a + b + 2 ) ;
г ) 2a³ + 2a²b + 2ab + 2b² - a - b = (2a³ + 2a²b)+ (2ab + 2b²)- (a + b) =
= 2a²( a + b ) + 2b( a + b ) - ( a + b ) = ( a + b )( 2a² + 2b - 1 ) .
