-4/9x²+4/3xy+y²

问题描述:

-4/9x²+4/3xy+y²

-4/9x²+4/3xy+y²=-4/9(x²-3xy)+y²=-4/9(x-3y/2)²+2y²=2y²-4/9(x-3y/2)²=2y²-(2x/3-y)²=(√2y-2x/3+y)(√2y+2x/3-y)祝你开心