x=2 y=1/2
所以xy=1
所以(3xy²)³*[xy(2x-y)-2x(xy-y²)]
=(3y)³*[(2x-y)-2x(1-y²)]
=27y³*(2x-y-2x+2xy²)
=27y³*(-y+2y)
=27y⁴
=27*(1/2)⁴
=27/16
如果不懂,祝学习愉快!
x=2 y=1/2
所以xy=1
所以(3xy²)³*[xy(2x-y)-2x(xy-y²)]
=(3y)³*[(2x-y)-2x(1-y²)]
=27y³*(2x-y-2x+2xy²)
=27y³*(-y+2y)
=27y⁴
=27*(1/2)⁴
=27/16
如果不懂,祝学习愉快!