先化简,在求值。3X^2+(-3⼀2X+1⼀3Y^2)(2X-2⼀3Y),其中X=-1⼀3,Y=2⼀3

2025-02-24 04:04:55
推荐回答(2个)
回答1:

3X^2+(-3/2X+1/3Y^2)(2X-2/3Y),
=3X^2-3X^2+xy+2/3xY^2-2/9Y^3
=xy+2/3xY^2-2/9Y^3
=-1/3*2/3-2/3*1/3*4/9-2/9*8/27
=-94/243

回答2: