Question

这道题怎么做？求答案，谢谢。

Answer 1

Answer 2

解:(1)8a²b+2a²b一3b²一4a²b一ab²
=(8a²b+2a²b一4a²b)一3b²一ab²
=6a²b一3b²一ab²
=b(6a²一3b一ab)

(2)1/3m²n一1/2mn²一nm²十1/6n²m
=(1/3m²n一m²n)十(1/6n²m一1/2n²m)
=一2/3m²n一1/3mn²
=一1/3mn(2m十n)

(3)一0.8a²b一6ab一1.2a²b十5ab十a²b
=(一0.8a²b一1.2a²b十a²b)一(6ab一5ab)
=一a²b一ab
=一ab(a一1)

(4)2(x²一2xy十y²)一(x²一4Xy一y²)
=2X²一4xy十2y²一x²十4xy十y²
=X²十3y²

化简:
(2x²一2y²)一3(x²y²十x²)+3(x²y²十y²)
=2x²一2y²一3x²y²一3x²十3x²y²十3y²
=一x²十y²
把x=一1，y=2代入上式得
一(一1)²十(2)²
=一1十4
=3

Answer 3

答案是在纸上面